btrfs: rename err to ret in __btrfs_end_transaction()

Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/transaction.c

@@ -1052,7 +1052,7 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
 {
 	struct btrfs_fs_info *info = trans->fs_info;
 	struct btrfs_transaction *cur_trans = trans->transaction;
-	int err = 0;
+	int ret = 0;
 
 	if (refcount_read(&trans->use_count) > 1) {
 		refcount_dec(&trans->use_count);
@@ -1091,13 +1091,13 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
 	if (TRANS_ABORTED(trans) || BTRFS_FS_ERROR(info)) {
 		wake_up_process(info->transaction_kthread);
 		if (TRANS_ABORTED(trans))
-			err = trans->aborted;
+			ret = trans->aborted;
 		else
-			err = -EROFS;
+			ret = -EROFS;
 	}
 
 	kmem_cache_free(btrfs_trans_handle_cachep, trans);
-	return err;
+	return ret;
 }
 
 int btrfs_end_transaction(struct btrfs_trans_handle *trans)