Fix SPDX license header (#231)

This change adds SPDX license headers to all files and eforces it with
the linter.

Signed-off-by: Philip Laine <philip.laine@gmail.com>

api/v1/groupversion_info.go

@@ -1,18 +1,4 @@
-/*
-Copyright 2025.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
+// SPDX-License-Identifier: BSD-3-Clause
 
 // Package v1 contains API Schema definitions for the  v1 API group.
 // +kubebuilder:object:generate=true

api/v1/nbgroup_types.go

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
 package v1
 
 import (

api/v1/nbpolicy_types.go

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
 package v1
 
 import (

api/v1/nbresource_types.go

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
 package v1
 
 import (

api/v1/nbroutingpeer_types.go

@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
 package v1
 
 import (

api/v1/nbsetupkey_types.go

@@ -1,18 +1,4 @@
-/*
-Copyright 2025.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
+// SPDX-License-Identifier: BSD-3-Clause
 
 package v1
 

api/v1/zz_generated.deepcopy.go

@@ -1,5 +1,7 @@
 //go:build !ignore_autogenerated
 
+// SPDX-License-Identifier: BSD-3-Clause
+
 // Code generated by controller-gen. DO NOT EDIT.
 
 package v1