KVM: arm64: nv: Add new HDFGRTR2_GROUP & HDFGRTR2_GROUP based FGU handling

This adds new HDFGRTR2_GROUP and HDFGWTR2_GROUP groups in enum fgt_group_id
for FGU handling managed with HDFGRTR2_EL2 and HDFGWTR2_EL2 registers.

Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: kvmarm@lists.linux.dev
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>