drm/i915: Update the dispatch tracepoint to use params->request

Updated a couple of trace points to use the now cached request pointer rather
than extracting it from the ring.

For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 8af3588..d94c015 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -944,7 +944,7 @@
 	if (ret)
 		return ret;
 
-	trace_i915_gem_ring_dispatch(intel_ring_get_request(ring), params->dispatch_flags);
+	trace_i915_gem_ring_dispatch(params->request, params->dispatch_flags);
 
 	i915_gem_execbuffer_move_to_active(vmas, ring);
 	i915_gem_execbuffer_retire_commands(params);