Add missing dependencies / alternatives

A number of places lacked the necessary dependencies on one of
the used features: MD, key exchange with certificate, 
entropy, or ETM.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/programs/ssl/ssl_context_info.c b/programs/ssl/ssl_context_info.c
index 19054eb..24d4b6a 100644
--- a/programs/ssl/ssl_context_info.c
+++ b/programs/ssl/ssl_context_info.c
@@ -645,7 +645,7 @@
         {
             printf( "\tcipher         : %s\n", cipher_info->name );
         }
-
+#if defined(MBEDTLS_MD_C)
         md_info = mbedtls_md_info_from_type( ciphersuite_info->mac );
         if( md_info == NULL )
         {
@@ -655,6 +655,7 @@
         {
             printf( "\tMessage-Digest : %s\n", mbedtls_md_get_name( md_info ) );
         }
+#endif
     }
 
     CHECK_SSL_END( 1 );