xfs: use kmem_free to free return value of kmem_zalloc

In function xfs_test_remount_options(), kfree() is used to free memory
allocated by kmem_zalloc(). But it is better to use kmem_free().

Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/xfs/xfs_super.c

@@ -1220,7 +1220,7 @@ xfs_test_remount_options(
 	tmp_mp->m_super = sb;
 	error = xfs_parseargs(tmp_mp, options);
 	xfs_free_fsname(tmp_mp);
-	kfree(tmp_mp);
+	kmem_free(tmp_mp);
 
 	return error;
 }