qemu_kill_report: Report PID name too

qemu_kill_report: Report PID name too

When qemu is being killed, its last words are:

2016-08-31T11:48:15.293587Z qemu-system-x86_64: terminating on signal 15 from pid 11180

That's nice, but what process is 11180? What if I told you we can
do better:

2016-08-31T11:48:15.293587Z qemu-system-x86_64: terminating on signal 15 from pid 11180 (/usr/sbin/libvirtd)

And that's exactly what this patch does.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Message-Id: <a2ba85a8e349a0ea9ee06424226197a03cd04bd3.1474987617.git.mprivozn@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>