kzalloc_obj with __GFP_NOFAIL is documented to never return failure,
and checking for NULL is redundant (__GFP_NOFAIL in gfp_types.h).
Signed-off-by: Li Wang <liwang@kylinos.cn>
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>