MGMT-19280: iSCSI colume should be eligible on day2 (#6999)

Openshift version is empty when the cluster is day2.

This fix infer the openshift version from the infraenv when the cluster
is not available or is day2.

In this context, the only use of openshift version is to check if iSCSI
boot disk is supported (for OCP >= 4.15).

internal/hardware/validator.go

@@ -118,9 +118,14 @@ func (v *validator) DiskIsEligible(ctx context.Context, disk *models.Disk, infra
 	if cluster != nil {
 		requirements, err = v.GetClusterHostRequirements(ctx, cluster, host)
 		clusterVersion = cluster.OpenshiftVersion
+		if common.IsDay2Cluster(cluster) {
+			// infer Openshift version from the infraEnv is case of day2
+			// because cluster.OpenshiftVersion will be empty
+			clusterVersion = infraEnv.OpenshiftVersion
+		}
 	} else {
 		requirements, err = v.GetInfraEnvHostRequirements(ctx, infraEnv)
-		clusterVersion = ""
+		clusterVersion = infraEnv.OpenshiftVersion
 	}
 	if err != nil {
 		return nil, err

internal/hardware/validator_test.go

@@ -222,10 +222,19 @@ var _ = Describe("Disk eligibility", func() {
 		Expect(err).ToNot(HaveOccurred())
 		Expect(eligible).To(ContainElement("Drive type is iSCSI, it must be one of HDD, SSD, Multipath."))
 
-		By("Check infra env iSCSI is not eligible")
+		By("Check iSCSI is eligible on day2 cluster")
+		testDisk.Iscsi = &models.Iscsi{HostIPAddress: "4.5.6.7"}
+		cluster.Kind = swag.String(models.ClusterKindAddHostsCluster)
+		cluster.OpenshiftVersion = ""
+		infraEnv.OpenshiftVersion = "4.16"
+		eligible, err = hwvalidator.DiskIsEligible(ctx, &testDisk, infraEnv, &cluster, &host, inventory)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(eligible).To(BeEmpty())
+
+		By("Check infra env iSCSI is eligible")
 		eligible, err = hwvalidator.DiskIsEligible(ctx, &testDisk, infraEnv, nil, &host, inventory)
 		Expect(err).ToNot(HaveOccurred())
-		Expect(eligible).To(ContainElement("Drive type is iSCSI, it must be one of HDD, SSD, Multipath."))
+		Expect(eligible).To(BeEmpty())
 	})
 
 	It("Check that FC multipath is eligible", func() {