Fix cutils/ashmem.h copyright header.

The *kernel* header is "GPL-2.0 OR Apache-2.0", but the userspace
libcutils is just Apache-2.0 like all our code.

Test: builds
Change-Id: I25eef8eed16550f4010285479b21b502a2d1fc07

libcutils/include/cutils/ashmem.h

@@ -1,14 +1,20 @@
-/* cutils/ashmem.h
- **
- ** Copyright 2008 The Android Open Source Project
- **
- ** This file is dual licensed.  It may be redistributed and/or modified
- ** under the terms of the Apache 2.0 License OR version 2 of the GNU
- ** General Public License.
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * 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.
  */
 
-#ifndef _CUTILS_ASHMEM_H
-#define _CUTILS_ASHMEM_H
+#pragma once
 
 #include <stddef.h>
 
@@ -30,5 +36,3 @@ int ashmem_get_size_region(int fd);
 #ifdef __cplusplus
 }
 #endif
-
-#endif	/* _CUTILS_ASHMEM_H */