arm64: KVM: Add VGIC device control for arm64

arm64: KVM: Add VGIC device control for arm64

This fixes the build breakage introduced by
c07a0191ef2de1f9510f12d1f88e3b0b5cd8d66f and adds support for the device
control API and save/restore of the VGIC state for ARMv8.

The defines were simply missing from the arm64 header files and
uaccess.h must be implicitly imported from somewhere else on arm.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 2a2f3e269c75edf916de5967079069aeb6a601cb)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>