LU-13805 clio: Add write to sdio

LU-13805 clio: Add write to sdio

Unaligned DIO will need to know if an sdio is a write or
a read, so we add this info to the sub-dio.

Test-parameters: trivial
Signed-off-by: Patrick Farrell <pfarrell@whamcloud.com>
Change-Id: I8ee042ca5a0461db672ba98b7fa6c64b01a8bba2
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/49991
Reviewed-by: Zhenyu Xu <bobijam@hotmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Qian Yingjin <qian@ddn.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>