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

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

This patch does Hyper-V Synthetic interrupt
controller(Hyper-V SynIC) MSR's support and
migration. Hyper-V SynIC is enabled by cpu's
'hv-synic' option.

This patch does not allow cpu creation if
'hv-synic' option specified but kernel
doesn't support Hyper-V SynIC.

Changes v3:
* removed 'msr_hv_synic_version' migration because
it's value always the same
* moved SynIC msr's initialization into kvm_arch_init_vcpu

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]>