drm/i915/selftests: Fix live_workarounds to actually do resets
The test was missing some magic ingredients to actually trigger the
resets.
In case of the full reset we need the I915_RESET_HANDOFF flag set, and in
case of engine reset we need a busy request.
Thanks to Chris for helping with reset magic.
v2:
* Grab RPM ref over reset.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20181130095211.23849-1-tvrtko.ursulin@linux.intel.com