lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_lock

nlmsvc_lock calls nlmsvc_lookup_host to find a nlm_host struct. The
callers of this function, however, call nlmsvc_retrieve_args or
nlm4svc_retrieve_args, which also return a nlm_host struct.

Change nlmsvc_lock to take a host arg instead of calling
nlmsvc_lookup_host itself and change the callers to pass a pointer to
the nlm_host they've already found.

Since nlmsvc_testlock() now just uses the caller's reference, we no
longer need to get or release it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c
index e099f58..82dc908 100644
--- a/fs/lockd/svcproc.c
+++ b/fs/lockd/svcproc.c
@@ -175,7 +175,7 @@
 #endif
 
 	/* Now try to lock the file */
-	resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
+	resp->status = cast_status(nlmsvc_lock(rqstp, file, host, &argp->lock,
 					       argp->block, &argp->cookie));
 	if (resp->status == nlm_drop_reply)
 		rc = rpc_drop_reply;