ocfs2: relax BUG() to ocfs2_error() in __ocfs2_move_extent()

ocfs2: relax BUG() to ocfs2_error() in __ocfs2_move_extent()

In '__ocfs2_move_extent()', relax 'BUG()' to 'ocfs2_error()' just
to avoid crashing the whole kernel due to a filesystem corruption.

Fixes: 8f603e567aa7 ("Ocfs2/move_extents: move a range of extent.")
Link: https://lkml.kernel.org/r/20251009102349.181126-2-dmantipov@yandex.ru
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Closes: https://syzkaller.appspot.com/bug?extid=727d161855d11d81e411
Reported-by: syzbot+727d161855d11d81e411@syzkaller.appspotmail.com
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.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>