ext4: delete redundant uptodate check for buffer

The buffer uptodate state has been checked in function set_buffer_uptodate,
there is no need use buffer_uptodate before calling set_buffer_uptodate and
delete it.

Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Yang Guo <guoyang2@huawei.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/1617260610-29770-1-git-send-email-zhangshaokun@hisilicon.com


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