target-i386/hyperv: Hyper-V SynIC SINT routing and vcpu exit

target-i386/hyperv: Hyper-V SynIC SINT routing and vcpu exit

Hyper-V SynIC(synthetic interrupt controller) helpers for
Hyper-V SynIC irq routing setup, irq injection, irq ack
notifications event/message pages changes tracking for future use.

Signed-off-by: Andrey Smetanin <[email protected]>
Reviewed-by: Roman Kagan <[email protected]>
Signed-off-by: Denis V. Lunev <[email protected]>
CC: Paolo Bonzini <[email protected]>
CC: Richard Henderson <[email protected]>
CC: Eduardo Habkost <[email protected]>
CC: "Andreas Färber" <[email protected]>
CC: Marcelo Tosatti <[email protected]>
CC: Roman Kagan <[email protected]>
CC: Denis V. Lunev <[email protected]>
CC: [email protected]
Signed-off-by: Paolo Bonzini <[email protected]>