[Driver][DXC] Remove a bunch of options from DXC

Remove DXCOption from a whole bunch of options that we probably won't
support in the DXC driver. The initial clang-dxc support just made
everything that was a "CoreOption" available, regardless of whether it
made sense. Here I don't remove all of them, but this makes a dent on
making the list a bit more sensible. We can easily add or remove more
if they make sense later.

Differential Revision: https://reviews.llvm.org/D158037

Author: bogner