Ensure that my_errno is set if tmp disk quota is reached

Storage engines generally expects that my_errno is set in case of errors

sql/mysqld.cc

@@ -3805,6 +3805,7 @@ static int temp_file_size_cb_func(struct tmp_file_tracking *track,
       {
         global_tmp_space_used-= size_change;
         error= EE_GLOBAL_TMP_SPACE_FULL;
+        my_errno= ENOSPC;
         goto exit;
       }
       if (thd->status_var.tmp_space_used + size_change >
@@ -3813,6 +3814,7 @@ static int temp_file_size_cb_func(struct tmp_file_tracking *track,
       {
         global_tmp_space_used-= size_change;
         error= EE_LOCAL_TMP_SPACE_FULL;
+        my_errno= ENOSPC;
         goto exit;
       }
       set_if_bigger(global_status_var.max_tmp_space_used, cached_space);