Cleanup: remove Cycles advanced shading features toggle.

It's effectively always enabled, only not on some unsupported OpenCL devices.
For testing those it's not useful to disable these features. This is replaced
by the more fine grained feature toggles that we have now.

intern/cycles/device/device_cuda.cpp

@@ -2512,7 +2512,6 @@ void device_cuda_info(vector<DeviceInfo>& devices)
 		info.description = string(name);
 		info.num = num;
 
-		info.advanced_shading = (major >= 3);
 		info.has_half_images = (major >= 3);
 		info.has_volume_decoupled = false;