add some checks for fedration-apiserver options

Kubernetes-commit: 172ab88ce848d2c2e6c344535d3011d4ac558a37

pkg/server/options/admission.go

@@ -89,3 +89,8 @@ func (a *AdmissionOptions) ApplyTo(serverCfg *server.Config, pluginInitializers
 	serverCfg.AdmissionControl = admissionChain
 	return nil
 }
+
+func (a *AdmissionOptions) Validate() []error {
+	errs := []error{}
+	return errs
+}

pkg/server/options/feature.go

@@ -55,3 +55,8 @@ func (o *FeatureOptions) ApplyTo(c *server.Config) error {
 
 	return nil
 }
+
+func (o *FeatureOptions) Validate() []error {
+	errs := []error{}
+	return errs
+}