* Move back to C++ for OpenCL
* Refactor OpenCL code to work more like the CUDA code, add missing functions
* Deduplicate dequant kernels
* Add OpenCL compile options
* Use compile args for preprocessing constants
* Restore default platform + device selection by id behavior
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Co-authored-by: Johannes Gäßler <[email protected]>
Co-authored-by: Henri Vasserman <[email protected]>
