internal/cloud/gcp/compute: Add TDX_CAPABLE guest OS feature

Latest RHEL images (from 9.6 on) should be able to run as TDX guests.
CentOS guests also fully support it at the moment.

See: https://issues.redhat.com/browse/COS-3111
See: coreos/coreos-assembler#4006
See: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/5979

internal/cloud/gcp/compute.go

@@ -29,6 +29,18 @@ var GuestOsFeaturesRHEL9 []*computepb.GuestOsFeature = []*computepb.GuestOsFeatu
 	{Type: common.ToPtr(computepb.GuestOsFeature_GVNIC.String())},
 	{Type: common.ToPtr(computepb.GuestOsFeature_SEV_SNP_CAPABLE.String())},
 	{Type: common.ToPtr(computepb.GuestOsFeature_SEV_LIVE_MIGRATABLE_V2.String())},
+	{Type: common.ToPtr(computepb.GuestOsFeature_TDX_CAPABLE.String())},
+}
+
+// Guest OS Features for RHEL images up to RHEL9.5.
+// The TDX support was added since RHEL-9.6.
+var GuestOsFeaturesRHEL95 []*computepb.GuestOsFeature = []*computepb.GuestOsFeature{
+	{Type: common.ToPtr(computepb.GuestOsFeature_UEFI_COMPATIBLE.String())},
+	{Type: common.ToPtr(computepb.GuestOsFeature_VIRTIO_SCSI_MULTIQUEUE.String())},
+	{Type: common.ToPtr(computepb.GuestOsFeature_SEV_CAPABLE.String())},
+	{Type: common.ToPtr(computepb.GuestOsFeature_GVNIC.String())},
+	{Type: common.ToPtr(computepb.GuestOsFeature_SEV_SNP_CAPABLE.String())},
+	{Type: common.ToPtr(computepb.GuestOsFeature_SEV_LIVE_MIGRATABLE_V2.String())},
 }
 
 // Guest OS Features for RHEL9.1 images.
@@ -71,6 +83,14 @@ func GuestOsFeaturesByDistro(distroName string) []*computepb.GuestOsFeature {
 	// TODO: this should be updated for the dot-notation
 	case distroName == "rhel-91":
 		return GuestOsFeaturesRHEL91
+	case distroName == "rhel-92":
+		fallthrough
+	case distroName == "rhel-93":
+		fallthrough
+	case distroName == "rhel-94":
+		fallthrough
+	case distroName == "rhel-95":
+		return GuestOsFeaturesRHEL95
 	case strings.HasPrefix(distroName, "centos-9"):
 		fallthrough
 	case strings.HasPrefix(distroName, "rhel-9"):