virtlockd: improve initscripts

virtlockd: improve initscripts

- Use SIGUSR1, not SIGHUP, on reload. At present, virtlockd only
  responds to the former.

- Fix PID file for virtlockd.

- Do not start virtlockd in any runlevels by default. It needs to be
  explicitly selected in libvirt's qemu.conf anyway, so there is no
  need to have it running on all systems regardless.

- Fix chkconfig priorities to ensure virtlockd is started before
  libvirtd is started, and stopped after libvirtd is stopped.

- Add "Should-Start: virtlockd" to the libvirtd initscript's LSB header,
  for the same reason.

- Add "Default-Stop" to both libvirtd and virtlockd initscripts. LSB
  does not guarantee that this defaults to the inverse of
  "Default-Start".

Signed-off-by: Michael Chapman <mike@very.puzzling.org>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>