KVM: arm/arm64: vgic-new: Add PRIORITY registers handlers

The priority register handlers are shared between the v2 and v3
emulation, so their implementation goes into vgic-mmio.c, to be
easily referenced from the v3 emulation as well later.
There is a corner case when we change the priority of a pending
interrupt which we don't handle at the moment.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>

virt/kvm/arm/vgic/vgic-mmio.h

@@ -129,6 +129,13 @@ void vgic_mmio_write_sactive(struct kvm_vcpu *vcpu,
 			     gpa_t addr, unsigned int len,
 			     unsigned long val);
 
+unsigned long vgic_mmio_read_priority(struct kvm_vcpu *vcpu,
+				      gpa_t addr, unsigned int len);
+
+void vgic_mmio_write_priority(struct kvm_vcpu *vcpu,
+			      gpa_t addr, unsigned int len,
+			      unsigned long val);
+
 unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev);
 
 #endif