jbd2: remove unnedded "need_copy_out" in jbd2_journal_write_metadata_buffer

As we only need to copy out when we should do escape, need_copy_out
could be simply replaced by "do_escape".

Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240514112438.1269037-4-shikemeng@huaweicloud.com


Signed-off-by: Theodore Ts'o <tytso@mit.edu>