LU-16188 mdt: fix incompatible HSM request handling

LU-16188 mdt: fix incompatible HSM request handling

When the coordinator tries to send multiple hsm actions in
a single request, if one of the request fails incompat checks all the
requests are marked as STARTED but none of the requests are
sent to the agent.

Return EAGAIN from mdt_agent_hsm_send() so that the coordinator would
not mark the requests as STARTED. It would retry them later.

Add a sanity-hsm test.

Test-Parameters: trivial testlist=sanity-hsm
Change-Id: Id4fb858021be6dc6b0cbcf140c3f2051efce57ad
Signed-off-by: Jeya Ganesh Babu Jegatheesan <jeyaga@amazon.com>
Signed-off-by: Aurelien Degremont <degremoa@amazon.com>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/48658
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Sergey Cheremencev <scherementsev@ddn.com>
Reviewed-by: Nikitas Angelinas <nikitas.angelinas@hpe.com>
Reviewed-by: Etienne AUJAMES <eaujames@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>