ctdb-cluster-mutex: Separate out command and file handling

ctdb-cluster-mutex: Separate out command and file handling

This code is difficult to read and there really is no common code
between the 2 cases.  For example, there is no need to split a
filename into words.  Separating each of the 2 cases into its own
function makes the logic much easier to understand.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>
Autobuild-User(master): Amitay Isaacs <amitay@samba.org>
Autobuild-Date(master): Mon Feb 25 03:40:16 CET 2019 on sn-devel-144