If launching mdmon via systemctl fails, we fall back to the old method
of fork/exec. This allows for having mdmon launched via systemctl
which avoids problems with it getting killed by systemd due to it
ending up in the parent's cgroup (udev).
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>