NLM: Remove "proto" argument from lockd_up()

Clean up: Now that lockd_up() starts listeners for both transports, the
"proto" argument is no longer needed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>