Fix: scheduler: filter Pacemaker-supplied stonith parameters from secure hash

Pacemaker calculates "secure digests" of resource operations as hashes of
non-sensitive resource parameters, for use when running crm_simulate on
sanitized data sets.

Previously, the controller and scheduler could calculate different secure
digests for the same resource history entry for stonith resources. The
controller created its hash based on all resource parameters listed in the
agent meta-data. The scheduler created its hash based on all configured
resource parameters, which could include the special parameters (such as
"provides") that are interpreted directly by Pacemaker and not passed to the
agent.

Now, the scheduler excludes the special parameters before hashing. This avoids
the annoying situation where running crm_simulate on a sanitized data set shows
unnecessary stonith resource restarts.