hmp: fix qemu crash due to ioapic state dump w/ split irqchip

The qemu will crash when info ioapic through hmp if irqchip
is split. Below message is splat:

KVM_GET_IRQCHIP failed: Unknown error -6

This patch fix it by dumping the ioapic state from the qemu
emulated ioapic if irqchip is split.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Message-Id: <1474602456-3232-1-git-send-email-wanpeng.li@hotmail.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-ID: <20160923090824.GF15411@pxdev.xzpeter.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
