Revert "MAC field in Endpoint is optional (#223)"

This reverts commit b705a57.

Author: afritzler

api/v1alpha1/endpoint_types.go

@@ -10,7 +10,7 @@ import (
 // EndpointSpec defines the desired state of Endpoint
 type EndpointSpec struct {
 	// MACAddress is the MAC address of the endpoint.
-	MACAddress string `json:"macAddress,omitempty"`
+	MACAddress string `json:"macAddress"`
 	// IP is the IP address of the endpoint.
 	// +kubebuilder:validation:Type=string
 	// +kubebuilder:validation:Schemaless

config/crd/bases/metal.ironcore.dev_endpoints.yaml

@@ -57,6 +57,7 @@ spec:
                 type: string
             required:
             - ip
+            - macAddress
             type: object
           status:
             description: EndpointStatus defines the observed state of Endpoint