LU-8465 ext2fs: fix to set tail flags with pfsck enabled

LU-8465 ext2fs: fix to set tail flags with pfsck enabled

If any of block/inode bitmap block checksum error happen,
tail flag should be set properly.

However, we firstly set tail flags in each thread, after
threads finish we clear those tail problem wrongly.

This will make fsck miss bitmap checksum erors later,
patch try to fix the problem by move all this kind of
logic in read_bitmaps_range_end()

Signed-off-by: Wang Shilong <wshilong@ddn.com>
Change-Id: Ie605f4475d35f9ce7d040036d97988c6512cb8c9
Reviewed-on: https://review.whamcloud.com/40071
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>