minigbm: Remove (c) from copyright notice.

The pre-submit hook script checks that copyright messages don't
contain "(c)".

This CL removes "(c)" from all the copyrights header in minigbm
that still have it.

BUG=None
TEST=emerge-$BOARD minigbm.

Change-Id: I1922d9d29b78d124302d497310fe1c1cfd6fc695
Reviewed-on: https://chromium-review.googlesource.com/421588
Commit-Ready: David Reveman <reveman@chromium.org>
Commit-Ready: Daniele Castagna <dcastagna@chromium.org>
Tested-by: Daniele Castagna <dcastagna@chromium.org>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
diff --git a/drv.h b/drv.h
index 83d3b6a..9204475 100644
--- a/drv.h
+++ b/drv.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016 The Chromium OS Authors. All rights reserved.
+ * Copyright 2016 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */