Merge mbedtls 2.16.6 into baremetal

Conflicts:
mbedtls.doxyfile - PROJECT_NAME - mbed TLS v2.16.6 chosen.
doc_mainpage.h - mbed TLS v2.16.6 version chosen.
hmac_drbg.h - line 260, extended description chosen.
            - line 313, extended description chosen.
            - line 338, extended description chosen.
version.h - 2.16.6 chosen.
CMakeLists.txt - 2.16.6 chosen.
test_suite_version.data - 2.16.6 chosen.
Makefile - 141 - manual correction - baremetal version of C_SOURCE_FILES
                 with variables for directories plus 2.16.6 CTAGS addition.
pkparse.c - lines 846 onwards - the asn1_get_nonzero_mpi implementation chosen.
ssl_tls.c - line 5269 - edited manually, left the ret=0, because baremetal has
            a different behaviour since commit 87b5626, but added a debug
            message that's new in 2.16.6.    
all.sh:
- component_build_deprecated - chosen the refactored version from 2.16.6,
                               but with extra flags from baremetal.
- rest of the _no_xxx tests - merged make options to have PTHREAD=1 and
                              other changes from 2.16.6 (like -O1 instead of -O0).
- component_build_arm_none_eabi_gcc_no_64bit_multiplication - added 
                              TINYCRYPT_BUILD=0 to the 2.16.6 version of make.

x509/req_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
x509/crl_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
x509/cert_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_mail_client.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_pthread_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_fork_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_client1.c - line 54 - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_client2.c - line 54 - left baremetal log but with mbedtls_exit( 0 ) call.
              - line 132 - new options of both branches added.
              - skip close notify handled as in 2.16.6, but with `ssl` instead of `&ssl`.
              - Merged the 2.16.6 usage split with additional baremetal usages.
              - Merged options from baremetal and 2.16.6.
ssl_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_server2.c - Merged the 2.16.6 usage split with additional baremetal usages.
config.pl - fixed missing defines from the documentation, removed duplicates,
            and reorganised so that the documentation and excluded list
            are ordered in the same way.
test_suite_x509parse.data - only added the two new pathlen tests.
x509_crt.c - change the return code by removing
             MBEDTLS_ERR_X509_INVALID_EXTENSIONS, since it's added by
             x509_crt_frame_parse_ext not by an "or", but by "+=".
Changelog - Assigned all entries to appropriate sections.
ssl-opt.sh - line 8263 - merged options.
           - removed lines 1165 - 1176 - there was a duplicate test, probably
             an artifact of previous merges.
check-files.py - sticked to old formatting.

Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/programs/test/benchmark.c b/programs/test/benchmark.c
index 71bee47..6036393 100644
--- a/programs/test/benchmark.c
+++ b/programs/test/benchmark.c
@@ -43,7 +43,7 @@
 int main( void )
 {
     mbedtls_printf("MBEDTLS_TIMING_C not defined.\n");
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 #else
 
@@ -155,6 +155,16 @@
 
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C) && defined(MBEDTLS_MEMORY_DEBUG)
 
+/* How much space to reserve for the title when printing heap usage results.
+ * Updated manually as the output of the following command:
+ *
+ *  sed -n 's/.*[T]IME_PUBLIC.*"\(.*\)",/\1/p' programs/test/benchmark.c |
+ *      awk '{print length+2}' | sort -rn | head -n1
+ *
+ * This computes the maximum length of a title +2 (because we appends "/s").
+ * (If the value is too small, the only consequence is poor alignement.) */
+#define TITLE_SPACE 11
+
 #define MEMORY_MEASURE_INIT                                             \
     size_t max_used, max_blocks, max_bytes;                             \
     size_t prv_used, prv_blocks;                                        \
@@ -163,7 +173,8 @@
 
 #define MEMORY_MEASURE_PRINT( title_len )                               \
     mbedtls_memory_buffer_alloc_max_get( &max_used, &max_blocks );      \
-    for( ii = 12 - (title_len); ii != 0; ii-- ) mbedtls_printf( " " );  \
+    ii = TITLE_SPACE > (title_len) ? TITLE_SPACE - (title_len) : 1;     \
+    while( ii-- ) mbedtls_printf( " " );                                \
     max_used -= prv_used;                                               \
     max_blocks -= prv_blocks;                                           \
     max_bytes = max_used + MEM_BLOCK_OVERHEAD * max_blocks;             \
@@ -1018,7 +1029,7 @@
     fflush( stdout ); getchar();
 #endif
 
-    return( 0 );
+    mbedtls_exit( 0 );
 }
 
 #endif /* MBEDTLS_TIMING_C */