SUNRPC: Move clnt->cl_server into struct rpc_xprt

When the cl_xprt field is updated, the cl_server field will also have
to change.  Since the contents of cl_server follow the remote endpoint
of cl_xprt, just move that field to the rpc_xprt.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[ cel: simplify check_gss_callback_principal(), whitespace changes ]
[ cel: forward ported to 3.4 ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 4a122ae..2afe233 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -332,7 +332,6 @@
 int
 check_gss_callback_principal(struct nfs_client *clp, struct svc_rqst *rqstp)
 {
-	struct rpc_clnt *r = clp->cl_rpcclient;
 	char *p = svc_gss_principal(rqstp);
 
 	if (rqstp->rq_authop->flavour != RPC_AUTH_GSS)
@@ -353,7 +352,7 @@
 	if (memcmp(p, "nfs@", 4) != 0)
 		return 0;
 	p += 4;
-	if (strcmp(p, r->cl_server) != 0)
+	if (strcmp(p, clp->cl_hostname) != 0)
 		return 0;
 	return 1;
 }