gfs2: Switch to may_setattr in gfs2_setattr

The permission check in gfs2_setattr is an old and outdated version of
may_setattr().  Switch to the updated version.

Fixes fstest generic/079.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/gfs2/inode.c

@@ -1985,8 +1985,8 @@ static int gfs2_setattr(struct user_namespace *mnt_userns,
 	if (error)
 		goto out;
 
-	error = -EPERM;
-	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
+	error = may_setattr(&init_user_ns, inode, attr->ia_valid);
+	if (error)
 		goto error;
 
 	error = setattr_prepare(&init_user_ns, dentry, attr);