sms: don't try the generic SMS method if we got a timeout error

src/mm-sms.c

@@ -1014,6 +1014,12 @@ send_from_storage_ready (MMBaseModem *modem,
 
     response = mm_base_modem_at_command_finish (MM_BASE_MODEM (modem), res, &error);
     if (error) {
+        if (g_error_matches (error, MM_SERIAL_ERROR, MM_SERIAL_ERROR_RESPONSE_TIMEOUT)) {
+            g_simple_async_result_take_error (ctx->result, error);
+            sms_send_context_complete_and_free (ctx);
+            return;
+        }
+
         mm_dbg ("Couldn't send SMS from storage: '%s'; trying generic send...",
                 error->message);
         g_error_free (error);