KVM: arm64: nv: Expose FGT to nested guests

Now that we have FGT support, expose the feature to NV guests.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-27-maz@kernel.org

Author: Marc Zyngier

arch/arm64/kvm/nested.c

@@ -71,8 +71,9 @@ void access_nested_id_reg(struct kvm_vcpu *v, struct sys_reg_params *p,
 		break;
 
 	case SYS_ID_AA64MMFR0_EL1:
-		/* Hide ECV, FGT, ExS, Secure Memory */
-		val &= ~(GENMASK_ULL(63, 43)		|
+		/* Hide ECV, ExS, Secure Memory */
+		val &= ~(NV_FTR(MMFR0, ECV)		|
+			 NV_FTR(MMFR0, EXS)		|
 			 NV_FTR(MMFR0, TGRAN4_2)	|
 			 NV_FTR(MMFR0, TGRAN16_2)	|
 			 NV_FTR(MMFR0, TGRAN64_2)	|