KVM: arm64: nv: Add handling of EL2-specific timer registers

Add the required handling for EL2 and EL02 registers, as
well as EL1 registers used in the E2H context. This includes
handling the virtual timer accesses when CNTHCTL_EL2.EL1TVT
or CNTHCTL_EL2.EL1TVCT are set.

Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20241217142321.763801-2-maz@kernel.org


Signed-off-by: Marc Zyngier <maz@kernel.org>