Added generic panic handler qemu_system_guest_panicked()

There are pieces of guest panic handling code
that can be shared in one generic function.
These code replaced by call qemu_system_guest_panicked().

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Andreas FÃ¤rber <afaerber@suse.de>
Message-Id: <1435924905-8926-10-git-send-email-den@openvz.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
