fs: dlm: cleanup and remove _send_rcom

The _send_rcom() can be removed and we call directly dlm_rcom_out().
As we doing that we removing the struct dlm_ls parameter which isn't
used.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>