SUNRPC: Rename rpcb_getport_external routine

In preparation for handling NFS mount option parsing in the kernel,
rename rpcb_getport_external as rpcb_get_port_sync, and make it available
always (instead of only when CONFIG_ROOT_NFS is enabled).

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c
index 49d1008..f0db470 100644
--- a/fs/nfs/nfsroot.c
+++ b/fs/nfs/nfsroot.c
@@ -428,7 +428,7 @@
 	printk(KERN_NOTICE "Looking up port of RPC %d/%d on %u.%u.%u.%u\n",
 		program, version, NIPQUAD(servaddr));
 	set_sockaddr(&sin, servaddr, 0);
-	return rpcb_getport_external(&sin, program, version, proto);
+	return rpcb_getport_sync(&sin, program, version, proto);
 }