LU-13805 llite: Implement unaligned DIO connect flag

LU-13805 llite: Implement unaligned DIO connect flag

Unupgraded ZFS servers may crash if they received unaligned
DIO, so we need a compat flag and a test to recognize those
servers.

This patch implements that logic.

Fixes: 7194eb6431 ("LU-13805 clio: bounce buffer for unaligned DIO")
Signed-off-by: Patrick Farrell <pfarrell@whamcloud.com>
Change-Id: I5d6ee3fa5dca989c671417f35a981767ee55d6e2
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/51126
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>