Clean up and minor fixes following review

Minor fixes following review including:
    * formatting changes including indentation and code style
    * corrections
    * removal of debug code
    * clarification of code through variable renaming
    * memory leak
    * compiler warnings
diff --git a/tests/suites/test_suite_cmac.function b/tests/suites/test_suite_cmac.function
index 81a5a0a..3b23b52 100644
--- a/tests/suites/test_suite_cmac.function
+++ b/tests/suites/test_suite_cmac.function
@@ -31,7 +31,7 @@
                     != NULL );
 
     TEST_ASSERT( result == mbedtls_cipher_cmac( cipher_info, key, key_size,
-                                                buf, 16, tmp ) != 0 );
+                                                buf, 16, tmp ) );
 }
 /* END_CASE */