drm/i915/selftests: Fill in a little more of the dummy fence

Initialise the dma_fence innards in preparation for making
dma_fence_signal() always check the callback list.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190708113038.19251-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/gt/selftest_lrc.c

@@ -859,6 +859,10 @@ static struct i915_request *dummy_request(struct intel_engine_cs *engine)
 	i915_sw_fence_init(&rq->submit, dummy_notify);
 	set_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags);
 
+	spin_lock_init(&rq->lock);
+	rq->fence.lock = &rq->lock;
+	INIT_LIST_HEAD(&rq->fence.cb_list);
+
 	return rq;
 }