NFSv4: Don't use cred->cr_ops->cr_name in nfs4_proc_setclientid()

With the recent change to generic creds, we can no longer use
cred->cr_ops->cr_name to distinguish between RPCSEC_GSS principals and
AUTH_SYS/AUTH_NULL identities. Replace it with the rpc_authops->au_name
instead...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

include/linux/sunrpc/auth.h

@@ -96,9 +96,7 @@ struct rpc_auth {
 struct rpc_authops {
 	struct module		*owner;
 	rpc_authflavor_t	au_flavor;	/* flavor (RPC_AUTH_*) */
-#ifdef RPC_DEBUG
 	char *			au_name;
-#endif
 	struct rpc_auth *	(*create)(struct rpc_clnt *, rpc_authflavor_t);
 	void			(*destroy)(struct rpc_auth *);