nfsd: reduce some spinlocking in put_client_renew

No need to take the lock unless the count goes to 0.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
1 file changed