KVM: PPC: booke: deliver program int on emulation failure

When we fail to emulate an instruction for the guest, we better go in and
tell it that we failed to emulate it, by throwing an illegal instruction
exception.

Please beware that we basically never get around to telling the guest that
we failed thanks to the debugging code right above it. If user space however
decides that it wants to ignore the debug, we would at least do "the right
thing" afterwards.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>