quota: Move definition of QFMT_OCFS2 to linux/quota.h

Move definition of this constant to linux/quota.h so that it
cannot clash with other format IDs.

CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/include/linux/quota.h b/include/linux/quota.h
index f63c9d6..7db3a00 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -73,6 +73,7 @@
 /* Quota format type IDs */
 #define	QFMT_VFS_OLD 1
 #define	QFMT_VFS_V0 2
+#define QFMT_OCFS2 3
 
 /* Size of block in which space limits are passed through the quota
  * interface */