libext2fs: change mmp.c to LGPL to match other files

Change the license of the mmp.c file to LGPL to match the license
of other files in the libext2fs library.

Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/lib/ext2fs/mmp.c b/lib/ext2fs/mmp.c
index bb3772d..435c5f4 100644
--- a/lib/ext2fs/mmp.c
+++ b/lib/ext2fs/mmp.c
@@ -4,8 +4,8 @@
  * Copyright (C) 2011 Whamcloud, Inc.
  *
  * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
  * %End-Header%
  */