Please be careful when touching sc/source/core/opencl

Hey,

so it seems like we have had a regression from some code cleanup in
sc/source/core/opencl and since the directory is under heavy development
and the test is disabled I would ask anyone to wait with any unncessary
clean-up in the directory.

Hopefully I can enable the automatic test soon again but for now it is
quite dangerous to touch this code if you don't know how to test your
changes. This is of course only a temporary solution but until I can fix
the build breakers with some OpenCL compilers we are working without a
safety net in this directory.

Of course fixing a build breaker is highly appreciated.

Thanks for your help keeping the OpenCL code clean,
Markus