init scripts: Do not kill per-domain qemu processes.

init scripts: Do not kill per-domain qemu processes.

Drop 2nd start-stop-daemon from qemu_stop_real xen init script.
Closes:#879751.

This code was introduced in
  8ad8a8221d9884b76f6942acabd9465e11ca23bd
  Start a qemu process in dom0 to service the toolstacks loopback disk attaches.

Ie the commit which introduced the global qemu.  There is no
indication that there was any intent to do anything to the per-domain
qemus.

I think the 2nd s-s-d invocation is there to stop a qemu which is for
some reason not mentioned in the pidfile and somehow escaped.  That
seems like a thing we should try to prevent.  I don't think if it
comes to pass, that it can be cleaned up without trashing the domUs.

So remove it.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>