Squashfs: get rid of obsolete definition in header file

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
index 36e1604..7902424 100644
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -183,8 +183,6 @@
 #define SQUASHFS_MAX_FILE_SIZE		(1LL << \
 					(SQUASHFS_MAX_FILE_SIZE_LOG - 2))
 
-#define SQUASHFS_MARKER_BYTE		0xff
-
 /* meta index cache */
 #define SQUASHFS_META_INDEXES	(SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
 #define SQUASHFS_META_ENTRIES	127