Cycles: Disable QBVH on 32bit systems all together

The reason for this is that we don't sue SSE optimization for 32bit platforms
because of T36316.

Things to look into:

- Nail the root of the issue of that report
- Implement non-SSE traversal code for QBVH

intern/cycles/blender/blender_sync.cpp

@@ -378,10 +378,13 @@ SceneParams BlenderSync::get_scene_params(BL::Scene b_scene, bool background, bo
 	else
 		params.persistent_data = false;
 
+#if !(defined(__GNUC__) && (defined(i386) || defined(_M_IX86)))
 	if(is_cpu) {
 		params.use_qbvh = system_cpu_support_sse2();
 	}
-	else {
+	else
+#endif
+	{
 		params.use_qbvh = false;
 	}