Remove lingering build code referencing the crypto submodule

Remove code guarded by `USE_CRYPTO_SUBMODULE`. It's dead now that
crypto can no longer be a submodule.

In `library/Makefile`:

* Replace `$(CRYPTO_INCLUDE)` with the single include directory
  `-I../include`.
* Remove references to `$(OBJS_CRYPTO)` when it's in addition to the
  local objects (`*.o`) since `$(OBJS_CRYPTO)` is now a subset of the
  local objects.
* Merge modules that were duplicated between the mbedtls and the
  mbed-crypto repositories back into the single list for `OBJS_CRYPTO`.
diff --git a/library/CMakeLists.txt b/library/CMakeLists.txt
index d23921a..a448442 100644
--- a/library/CMakeLists.txt
+++ b/library/CMakeLists.txt
@@ -171,23 +171,17 @@
     target_include_directories(${mbedcrypto_static_target}
         PUBLIC ${MBEDTLS_DIR}/include/)
 
-    if(USE_CRYPTO_SUBMODULE)
-        install(TARGETS ${mbedcrypto_static_target}
-                DESTINATION ${LIB_INSTALL_DIR}
-                PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
-    else()
-        add_library(${mbedx509_static_target} STATIC ${src_x509})
-        set_target_properties(${mbedx509_static_target} PROPERTIES OUTPUT_NAME mbedx509)
-        target_link_libraries(${mbedx509_static_target} ${libs} ${mbedcrypto_static_target})
+    add_library(${mbedx509_static_target} STATIC ${src_x509})
+    set_target_properties(${mbedx509_static_target} PROPERTIES OUTPUT_NAME mbedx509)
+    target_link_libraries(${mbedx509_static_target} ${libs} ${mbedcrypto_static_target})
 
-        add_library(${mbedtls_static_target} STATIC ${src_tls})
-        set_target_properties(${mbedtls_static_target} PROPERTIES OUTPUT_NAME mbedtls)
-        target_link_libraries(${mbedtls_static_target} ${libs} ${mbedx509_static_target})
+    add_library(${mbedtls_static_target} STATIC ${src_tls})
+    set_target_properties(${mbedtls_static_target} PROPERTIES OUTPUT_NAME mbedtls)
+    target_link_libraries(${mbedtls_static_target} ${libs} ${mbedx509_static_target})
 
-        install(TARGETS ${mbedtls_static_target} ${mbedx509_static_target} ${mbedcrypto_static_target}
-                DESTINATION ${LIB_INSTALL_DIR}
-                PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
-    endif()
+    install(TARGETS ${mbedtls_static_target} ${mbedx509_static_target} ${mbedcrypto_static_target}
+            DESTINATION ${LIB_INSTALL_DIR}
+            PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
 endif(USE_STATIC_MBEDTLS_LIBRARY)
 
 if(USE_SHARED_MBEDTLS_LIBRARY)
@@ -210,33 +204,20 @@
     target_include_directories(mbedtls
         PUBLIC ${MBEDTLS_DIR}/include/)
 
-    if(USE_CRYPTO_SUBMODULE)
-        install(TARGETS mbedcrypto
-                DESTINATION ${LIB_INSTALL_DIR}
-                PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
-    else()
-        add_library(mbedx509 SHARED ${src_x509})
-        set_target_properties(mbedx509 PROPERTIES VERSION 2.16.0 SOVERSION 0)
-        target_link_libraries(mbedx509 ${libs} mbedcrypto)
+    add_library(mbedx509 SHARED ${src_x509})
+    set_target_properties(mbedx509 PROPERTIES VERSION 2.16.0 SOVERSION 0)
+    target_link_libraries(mbedx509 ${libs} mbedcrypto)
 
-        add_library(mbedtls SHARED ${src_tls})
-        set_target_properties(mbedtls PROPERTIES VERSION 2.16.0 SOVERSION 12)
-        target_link_libraries(mbedtls ${libs} mbedx509)
+    add_library(mbedtls SHARED ${src_tls})
+    set_target_properties(mbedtls PROPERTIES VERSION 2.16.0 SOVERSION 12)
+    target_link_libraries(mbedtls ${libs} mbedx509)
 
-        install(TARGETS mbedtls mbedx509 mbedcrypto
-                DESTINATION ${LIB_INSTALL_DIR}
-                PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
-    endif()
+    install(TARGETS mbedtls mbedx509 mbedcrypto
+            DESTINATION ${LIB_INSTALL_DIR}
+            PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
 endif(USE_SHARED_MBEDTLS_LIBRARY)
 
-if(USE_CRYPTO_SUBMODULE)
-    add_custom_target(crypto_lib DEPENDS mbedcrypto)
-    if(USE_STATIC_MBEDTLS_LIBRARY AND USE_SHARED_MBEDTLS_LIBRARY)
-        add_dependencies(crypto_lib mbedcrypto_static)
-    endif()
-else()
-    add_custom_target(lib DEPENDS mbedcrypto mbedx509 mbedtls)
-    if(USE_STATIC_MBEDTLS_LIBRARY AND USE_SHARED_MBEDTLS_LIBRARY)
-        add_dependencies(lib mbedcrypto_static mbedx509_static mbedtls_static)
-    endif()
+add_custom_target(lib DEPENDS mbedcrypto mbedx509 mbedtls)
+if(USE_STATIC_MBEDTLS_LIBRARY AND USE_SHARED_MBEDTLS_LIBRARY)
+    add_dependencies(lib mbedcrypto_static mbedx509_static mbedtls_static)
 endif()
diff --git a/library/Makefile b/library/Makefile
index 07247f1..e4f92e5 100644
--- a/library/Makefile
+++ b/library/Makefile
@@ -5,8 +5,7 @@
 WARNING_CFLAGS ?=  -Wall -Wextra
 LDFLAGS ?=
 
-CRYPTO_INCLUDES ?= -I../include
-LOCAL_CFLAGS = $(WARNING_CFLAGS) $(CRYPTO_INCLUDES) -D_FILE_OFFSET_BITS=64
+LOCAL_CFLAGS = $(WARNING_CFLAGS) -I../include -D_FILE_OFFSET_BITS=64
 LOCAL_LDFLAGS =
 
 ifdef DEBUG
@@ -73,7 +72,7 @@
 		dhm.o		ecdh.o		ecdsa.o		\
 		ecjpake.o	ecp.o				\
 		ecp_curves.o	entropy.o	entropy_poll.o	\
-		gcm.o		havege.o			\
+		error.o		gcm.o		havege.o	\
 		hkdf.o						\
 		hmac_drbg.o	md.o		md2.o		\
 		md4.o		md5.o				\
@@ -89,20 +88,9 @@
 		ripemd160.o	rsa_internal.o	rsa.o  		\
 		sha1.o		sha256.o	sha512.o	\
 		threading.o	timing.o			\
+		version.o	version_features.o		\
 		xtea.o
 
-# For files generated by the parent project (Mbed TLS) when building Mbed
-# Crypto as a submodule, ensure that the parent project instance is used.
-ifeq ($(USE_CRYPTO_SUBMODULE), 1)
-OBJS_CRYPTO += $(patsubst %.c,%.o, $(realpath ../../library/error.c))
-OBJS_CRYPTO += $(patsubst %.c,%.o, $(realpath ../../library/version.c))
-OBJS_CRYPTO += $(patsubst %.c,%.o, $(realpath ../../library/version_features.c))
-else
-OBJS_CRYPTO += error.o
-OBJS_CRYPTO += version.o
-OBJS_CRYPTO += version_features.o
-endif
-
 include ../3rdparty/Makefile.inc
 LOCAL_CFLAGS+=$(THIRDPARTY_INCLUDES)
 OBJS_CRYPTO+=$(THIRDPARTY_CRYPTO_OBJECTS)
@@ -221,9 +209,8 @@
 
 clean:
 ifndef WINDOWS
-	rm -f *.o libmbed* $(OBJS_CRYPTO)
+	rm -f *.o libmbed*
 else
 	if exist *.o del /Q /F *.o
 	if exist libmbed* del /Q /F libmbed*
-	if exist $(OBJS_CRYPTO) del /Q /F $(OBJS_CRYPTO)
 endif