Fix small issues in tests found by Coverity
diff --git a/tests/suites/test_suite_md.function b/tests/suites/test_suite_md.function
index 099d109..0fcaa38 100644
--- a/tests/suites/test_suite_md.function
+++ b/tests/suites/test_suite_md.function
@@ -359,7 +359,7 @@
md_info = mbedtls_md_info_from_string( md_name );
TEST_ASSERT( md_info != NULL );
- mbedtls_md_file( md_info, filename, output);
+ TEST_ASSERT( mbedtls_md_file( md_info, filename, output ) == 0 );
hexify( hash_str, output, mbedtls_md_get_size(md_info) );
TEST_ASSERT( strcmp( (char *) hash_str, hex_hash_string ) == 0 );