Remove use of the macro TEST_FN from the AES test suite

The TEST_FN macro is now redundant and no longer necessary.
diff --git a/tests/suites/test_suite_aes.function b/tests/suites/test_suite_aes.function
index 24b5e4d..062234b 100644
--- a/tests/suites/test_suite_aes.function
+++ b/tests/suites/test_suite_aes.function
@@ -16,7 +16,7 @@
 
     memset(output, 0x00, 100);
 
-    TEST_FN( mbedtls_aes_init( &ctx ) );
+    mbedtls_aes_init( &ctx );
 
     TEST_ASSERT( mbedtls_aes_setkey_enc( &ctx, key_str->x, key_str->len * 8 ) == setkey_result );
     if( setkey_result == 0 )
@@ -40,7 +40,7 @@
 
     memset(output, 0x00, 100);
 
-    TEST_FN( mbedtls_aes_init( &ctx ) );
+    mbedtls_aes_init( &ctx );
 
     TEST_ASSERT( mbedtls_aes_setkey_dec( &ctx, key_str->x, key_str->len * 8 ) == setkey_result );
     if( setkey_result == 0 )
@@ -65,7 +65,7 @@
 
     memset(output, 0x00, 100);
 
-    TEST_FN( mbedtls_aes_init( &ctx ) );
+    mbedtls_aes_init( &ctx );
 
     mbedtls_aes_setkey_enc( &ctx, key_str->x, key_str->len * 8 );
     TEST_ASSERT( mbedtls_aes_crypt_cbc( &ctx, MBEDTLS_AES_ENCRYPT, src_str->len, iv_str->x, src_str->x, output ) == cbc_result );
@@ -393,7 +393,6 @@
     TEST_INVALID_PARAM_RET( MBEDTLS_ERR_AES_BAD_INPUT_DATA,
                             mbedtls_aes_setkey_dec( &dummy_ctx, NULL, 128 ) );
 
-
 exit:
     return;
 }