Merge pull request #42717 from andrewsykim/support-host-ip-downward-api

Automatic merge from submit-queue

Support status.hostIP in downward API

**What this PR does / why we need it**:
Exposes pod's hostIP (node IP) via downward API. 

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: 
fixes https://github.com/kubernetes/kubernetes/issues/24657

**Special notes for your reviewer**:
Not sure if there's more documentation that's needed, please point me in the right direction and I will add some :)

pkg/generated/openapi/zz_generated.openapi.go

@@ -3355,7 +3355,7 @@ func GetOpenAPIDefinitions(ref openapi.ReferenceCallback) map[string]openapi.Ope
 					Properties: map[string]spec.Schema{
 						"fieldRef": {
 							SchemaProps: spec.SchemaProps{
-								Description: "Selects a field of the pod: supports metadata.name, metadata.namespace, metadata.labels, metadata.annotations, spec.nodeName, spec.serviceAccountName, status.podIP.",
+								Description: "Selects a field of the pod: supports metadata.name, metadata.namespace, metadata.labels, metadata.annotations, spec.nodeName, spec.serviceAccountName, status.hostIP, status.podIP.",
 								Ref:         ref("k8s.io/kubernetes/pkg/api/v1.ObjectFieldSelector"),
 							},
 						},