btrfs: use GFP_KERNEL in btrfs_add/del_qgroup_relation

Qgroup relations are added/deleted from ioctl, we hold the high level
qgroup lock, no deadlocks or recursion from the allocation possible
here.
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/qgroup.c

@@ -1174,7 +1174,7 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
 	if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
 		return -EINVAL;
 
-	tmp = ulist_alloc(GFP_NOFS);
+	tmp = ulist_alloc(GFP_KERNEL);
 	if (!tmp)
 		return -ENOMEM;
 
@@ -1234,7 +1234,7 @@ int __del_qgroup_relation(struct btrfs_trans_handle *trans,
 	int ret = 0;
 	int err;
 
-	tmp = ulist_alloc(GFP_NOFS);
+	tmp = ulist_alloc(GFP_KERNEL);
 	if (!tmp)
 		return -ENOMEM;