ANDROID: arm64: Auto-enroll MMIO guard on protected vms

Set the MMIO guard flag for protected vms prior to entering the guest
for the first time.

Bug: 357781595
Change-Id: I1448102ae85176d495ae7f8d6d20de4092049f0d
Signed-off-by: Sebastian Ene <sebastianene@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>

arch/arm64/kvm/hyp/nvhe/pkvm.c

@@ -1028,6 +1028,9 @@ void pkvm_reset_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
 		/* PC: IPA of pvmfw base */
 		*vcpu_pc(&hyp_vcpu->vcpu) = entry;
 		hyp_vm->pvmfw_entry_vcpu = NULL;
+
+		/* Auto enroll MMIO guard */
+		set_bit(KVM_ARCH_FLAG_MMIO_GUARD, &hyp_vm->kvm.arch.flags);
 	}
 
 	reset_state->reset = false;