I updated to the latest src and it looks like there's been quite a few changes to integrate OpenCL/CUDA into LuxRender.
I did notice that there was a hard-coded path put in for the ATI Stream SDK, though.
Just to let you know that when you install the ATI Stream SDK, it will create an environment variable named ATISTREAMSDKROOT.
This should make it easier for users to compile LuxRender (particularly because the current location isn't at the default directory where the ATI Stream SDK installs).
OpenCL Includes location:
OpenCL lib directories:
I wouldn't be surprised if NVidia's CUDA SDK had something similar, too.