ext4: fix traditional comparison using max/min method

It would be better to replace the traditional ternary conditional
operator with max()/min()

Signed-off-by: Lu Hongfei <luhongfei@vivo.com>
Reviewed-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230529070930.37949-1-luhongfei@vivo.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>