SUNRPC: Simplify rpcb_register() API

Bruce suggested there's no need to expose the difference between an error
sending the PMAP_SET request and an error reply from the portmapper to
rpcb_register's callers.  The user space equivalent of rpcb_register() is
pmap_set(3), which returns a bool_t : either the PMAP set worked, or it
didn't.  Simple.

So let's remove the "*okay" argument from rpcb_register() and
rpcb_v4_register(), and simply return an error if any part of the call
didn't work.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 9ba1704..9805143 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -730,7 +730,7 @@
 	struct svc_program	*progp;
 	unsigned long		flags;
 	unsigned int		i;
-	int			error = 0, dummy;
+	int			error = 0;
 
 	if (!port)
 		clear_thread_flag(TIF_SIGPENDING);
@@ -751,13 +751,9 @@
 			if (progp->pg_vers[i]->vs_hidden)
 				continue;
 
-			error = rpcb_register(progp->pg_prog, i, proto, port, &dummy);
+			error = rpcb_register(progp->pg_prog, i, proto, port);
 			if (error < 0)
 				break;
-			if (port && !dummy) {
-				error = -EACCES;
-				break;
-			}
 		}
 	}