arm64/kvm: Add generic v8 KVM target

This patch adds a generic ARM v8 KVM target cpu type for use
by the new CPUs which eventualy ends up using the common sys_reg
table. For backward compatibility the existing targets have been
preserved. Any new target CPU that can be covered by generic v8
sys_reg tables should make use of the new generic target.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 48868d8..d250160 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -295,7 +295,8 @@
 		break;
 	};
 
-	return -EINVAL;
+	/* Return a default generic target */
+	return KVM_ARM_TARGET_GENERIC_V8;
 }
 
 int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)