SUNRPC: Fix another issue with rpc_client_register()

Fix the error pathway if rpcauth_create() fails.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 9963584..74f6a70 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -309,6 +309,7 @@
 	return 0;
 err_auth:
 	pipefs_sb = rpc_get_sb_net(net);
+	rpc_unregister_client(clnt);
 	__rpc_clnt_remove_pipedir(clnt);
 out:
 	if (pipefs_sb)