KVM: arm64: gic: Introduce interrupt type helpers

KVM: arm64: gic: Introduce interrupt type helpers

GICv5 has moved from using interrupt ranges for different interrupt
types to using some of the upper bits of the interrupt ID to denote
the interrupt type. This is not compatible with older GICs (which rely
on ranges of interrupts to determine the type), and hence a set of
helpers is introduced. These helpers take a struct kvm*, and use the
vgic model to determine how to interpret the interrupt ID.

Helpers are introduced for PPIs, SPIs, and LPIs. Additionally, a
helper is introduced to determine if an interrupt is private - SGIs
and PPIs for older GICs, and PPIs only for GICv5.

Additionally, vgic_is_v5() is introduced (which unsurpisingly returns
true when running a GICv5 guest), and the existing vgic_is_v3() check
is moved from vgic.h to arm_vgic.h (to live alongside the vgic_is_v5()
one), and has been converted into a macro.

The helpers are plumbed into the core vgic code, as well as the Arch
Timer and PMU code.

There should be no functional changes as part of this change.

Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Link: https://patch.msgid.link/20260319154937.3619520-10-sascha.bischoff@arm.com
Signed-off-by: Marc Zyngier <maz@kernel.org>