Freshclam: Minor error handling improvement

Somehow forgot to save and commit final error handling check on the new
set_tls_client_certificate() function.
This change is needed to have Freshclam fail if you try to use the new
client certificate environment variables incorrectly.

libfreshclam/libfreshclam_internal.c

@@ -732,7 +732,10 @@ static fc_error_t create_curl_handle(
 #endif
 
     /* Authenticate using a client certificate and private key, if specified by the FRESHCLAM_CLIENT_CERT, FRESHCLAM_CLIENT_KEY, and FRESHCLAM_CLIENT_KEY_PASSWD environment variables. */
-    set_tls_client_certificate(curl);
+    if (CL_SUCCESS != set_tls_client_certificate(curl)) {
+        logg(LOGG_DEBUG, "create_curl_handle: Failed to set certificate and private key for client authentiation.\n");
+        goto done;
+    }
 
     *curlHandle = curl;
     status      = FC_SUCCESS;