KVM Test: Add qemu_killer_report test script.

Automate the testcase named "QEMU
should report the PID of the process that sent it kill
signals test case"
that sent it kill signals

Signed-off-by: Feng Yang <fyang@redhat.com>
Acked-by: Xiaoqing Wei <xwei@redhat.com>
Acked-by: Qingtang Zhou <qzhou@redhat.com>
qemu: Use wait_for replace hardcode sleep time.

Signed-off-by: Feng Yang <fyang@redhat.com>