LU-10383 hsm: add action count to hsm scan data

LU-10383 hsm: add action count to hsm scan data

Add an 'hsm_action_count' member to struct hsm_scan_data to count the
total number of actions in all requests in the hsd. Add an 'hsd_'
prefix to all pre-existing members of struct hsm_scan_data.

Test-Parameters: trivial testlist=sanity-hsm
Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: Iab784a0f281d697bc0db758f20ce500315b8194a
Reviewed-on: https://review.whamcloud.com/31235
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Quentin Bouget <quentin.bouget@cea.fr>
Reviewed-by: Faccini Bruno <bruno.faccini@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>