drm/i915/gt: Stop poking at engine->serial at a high level

In record defaults, if we emit a request we expect a context switck on
parking. We need take no further action, so don't even mess with the low
level engine->serial where it is not warranted.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Acked-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191225230703.2498794-1-chris@chris-wilson.co.uk

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

@@ -410,14 +410,13 @@ static int __engines_record_defaults(struct intel_gt *gt)
 		struct intel_context *ce;
 		struct i915_request *rq;
 
+		/* We must be able to switch to something! */
+		GEM_BUG_ON(!engine->kernel_context);
+
 		err = intel_renderstate_init(&so, engine);
 		if (err)
 			goto out;
 
-		/* We must be able to switch to something! */
-		GEM_BUG_ON(!engine->kernel_context);
-		engine->serial++; /* force the kernel context switch */
-
 		ce = intel_context_create(engine);
 		if (IS_ERR(ce)) {
 			err = PTR_ERR(ce);