target-i386/kvm: Hyper-V SynIC timers MSR's support

Hyper-V SynIC timers are host timers that are configurable
by guest through corresponding MSR's (HV_X64_MSR_STIMER*).
Guest setup and use fired by host events(SynIC interrupt
and appropriate timer expiration message) as guest clock
events.

The state of Hyper-V SynIC timers are stored in corresponding
MSR's. This patch seria implements such MSR's support and migration.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Denis V. Lunev <den@openvz.org>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: kvm@vger.kernel.org

Message-Id: <1448464885-8300-3-git-send-email-asmetanin@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>