fs/ocfs2/dlm/dlmlock.c: free kmem_cache_zalloc'd data using kmem_cache_free

Memory allocated using kmem_cache_zalloc should be freed using
kmem_cache_free, not kfree.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/

)

// <smpl>
@@
expression x,e,e1,e2;
@@

x = kmem_cache_zalloc(e1,e2)
... when != x = e
?-kfree(x)
+kmem_cache_free(e1,x)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Joel Becker <jlbec@evilplan.org>