ocfs2: o2net_idle_timer: Rename del_timer_sync in comment

Commit 8fa7292f ("treewide: Switch/rename to timer_delete[_sync]()")
switched del_timer_sync to timer_delete_sync, but did not modify the
comment for o2net_idle_timer().  Now fix it.

Link: https://lkml.kernel.org/r/BDDB1E4E2876C36C+20250411102610.165946-1-wangyuli@uniontech.com


Signed-off-by: WangYuli <wangyuli@uniontech.com>
Acked-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>