Add initial test driver conforming to the new spec

Also adjusted the different makefiles accordingly.
Note: driver lifetime is currently statically defined in the header, but
this will be replaced in the future based on autogeneration of lifetime
values by a script (TBD)

Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8833246..5af4c81 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -261,7 +261,7 @@
 # to define the test executables.
 #
 if(ENABLE_TESTING OR ENABLE_PROGRAMS)
-    file(GLOB MBEDTLS_TEST_FILES ${CMAKE_CURRENT_SOURCE_DIR}/tests/src/*.c)
+    file(GLOB MBEDTLS_TEST_FILES ${CMAKE_CURRENT_SOURCE_DIR}/tests/src/*.c ${CMAKE_CURRENT_SOURCE_DIR}/tests/src/drivers/*.c)
     add_library(mbedtls_test OBJECT ${MBEDTLS_TEST_FILES})
     target_include_directories(mbedtls_test
         PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/tests/include