Fix gcc warning and Oops that it causes:

fs/ocfs2/cluster/masklog.c:161: warning: assignment from incompatible pointer type
[ 2776.204120] OCFS2 Node Manager 1.3.3
[ 2776.211729] BUG: spinlock bad magic on CPU#0, modprobe/4424
[ 2776.214269]  lock: ffff810021c8fe18, .magic: ffffffff, .owner: /6394416, .owner_cpu: 0
[ 2776.217864] [ 2776.217865] Call Trace:
[ 2776.219662]  [<ffffffff803426c8>] spin_bug+0x9e/0xe9
[ 2776.221921]  [<ffffffff803427bf>] _raw_spin_lock+0x23/0xf9
[ 2776.224417]  [<ffffffff8051acf4>] _spin_lock+0x9/0xb
[ 2776.226676]  [<ffffffff8033c3b1>] kobject_shadow_add+0x98/0x1ac
[ 2776.229367]  [<ffffffff8033c4d0>] kobject_add+0xb/0xd
[ 2776.231665]  [<ffffffff8033c4df>] kset_add+0xd/0xf
[ 2776.233845]  [<ffffffff8033c5a6>] kset_register+0x23/0x28
[ 2776.236309]  [<ffffffff8808ccb7>] :ocfs2_nodemanager:mlog_sys_init+0x68/0x6d
[ 2776.239518]  [<ffffffff8808ccee>] :ocfs2_nodemanager:o2cb_sys_init+0x32/0x4a
[ 2776.242726]  [<ffffffff880b80a6>] :ocfs2_nodemanager:init_o2nm+0xa6/0xd5
[ 2776.245772]  [<ffffffff8025266c>] sys_init_module+0x1471/0x15d2
[ 2776.248465]  [<ffffffff8033f250>] simple_strtoull+0x0/0xdc
[ 2776.250959]  [<ffffffff8020948e>] system_call+0x7e/0x83

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>