Updated dpcpp package (#27953)
Updated dpcpp package (#27953)

* Added installation of OpenMP as an option
* Added a softlink (dpcpp) to clang++ to
mimic the packaged version of dpcpp

Co-authored-by: ravil <a2bfa2c0f6a6569e0d530b318706d39d2fd5aef1@tum.de>
LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack