CP2K: arch file improvements and blas-dependency simplification (#16074)
CP2K: arch file improvements and blas-dependency simplification (#16074)

* cp2k: prettify arch-file, call pkg-config directly

this allows to re-use the arch-file without having to load the complete
Spack environment, for example after a dev-build

* cp2k: use consistency check instead of blas lib enum

this makes using other BLAS/LAPACK implementations possible without
explicitly adding support for them

* cp2k: add basic support for Cray and XL Compilers, correct Intel fp mode

* cp2k: add myself as maintainer

* cp2k: use "master" to denote the git version

* cp2k: use spack_cc/fc/cxx when possible, set CXX explicitly

* cp2k: set __MKL when using the MKL, not just the Intel compiler

* cp2k: drop self. when referencing spec where possible

* cp2k: add forgotten elpa+openmp dep

* cp2k: set C++14 for recent versions
iulian787/spack,LLNL/spack,LLNL/spack,LLNL/spack,iulian787/spack,iulian787/spack,iulian787/spack,LLNL/spack,LLNL/spack,iulian787/spack