drm/i915/gt: Replace 'return' with a fall-through

Checkpatch worries that the 'return' before an else clause might be
redundant. In this case, it is avoiding hitting the MISSING_CASE()
warning. Let us appease checkpatch by falling through to the end of the
function, which typically means that we then clean up the unused
wa_list.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210122192913.4518-10-chris@chris-wilson.co.ukSigned-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

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

@@ -757,7 +757,7 @@ __intel_engine_init_ctx_wa(struct intel_engine_cs *engine,
 	else if (IS_GEN(i915, 6))
 		gen6_ctx_workarounds_init(engine, wal);
 	else if (INTEL_GEN(i915) < 8)
-		return;
+		;
 	else
 		MISSING_CASE(INTEL_GEN(i915));
 
@@ -1209,7 +1209,7 @@ gt_init_workarounds(struct drm_i915_private *i915, struct i915_wa_list *wal)
 	else if (IS_GEN(i915, 4))
 		gen4_gt_workarounds_init(i915, wal);
 	else if (INTEL_GEN(i915) <= 8)
-		return;
+		;
 	else
 		MISSING_CASE(INTEL_GEN(i915));
 }
@@ -1584,7 +1584,7 @@ void intel_engine_init_whitelist(struct intel_engine_cs *engine)
 	else if (IS_SKYLAKE(i915))
 		skl_whitelist_build(engine);
 	else if (INTEL_GEN(i915) <= 8)
-		return;
+		;
 	else
 		MISSING_CASE(INTEL_GEN(i915));