LU-7668 utils: add lctl del_ost

LU-7668 utils: add lctl del_ost

Add helper command:

   lctl del_ost [--dryrun] --target fsname-OSTxxxx

Permanently disable an OST by altering the client and MDT llog
catalogs on MGS. The command finds all catalog records related to the
specified OST and cancel them. A --dryrun option is provided so that
the system administrator can see which records would have been
cancelled, but without actually cancelling them.

Lustre-change: https://review.whamcloud.com/41449
Lustre-commit: 1121816c4a4e1bb2ef097c4a9802362181c43800

LU-7668 tests: skip conf-sanity test_33a for old MGS

Skip del_ost test for MGS versions that do not have this command.

Lustre-change: https://review.whamcloud.com/50221
Lustre-commit: ba5346b050fb395844252a706d4dba2ef0e0d8dc

Signed-off-by: Stephane Thiell <sthiell@stanford.edu>
Change-Id: I58c4f10fa0f7164a40231e807698eb224cccf062
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/50923
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>