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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>