Add ABI documentation for these files:

	/sys/fs/ocfs2/max_locking_protocol
	/sys/fs/ocfs2/loaded_cluster_plugins
	/sys/fs/ocfs2/active_cluster_plugin
	/sys/fs/ocfs2/cluster_stack
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>