ocfs2/dlm: dlmdebug.c: make 2 functions static

This patch makes the following needlessly global functions static:
- stringify_lockname()
- dlm_debug_put()

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>