Should set `BLA_VENDOR` in CMakeMake easyblock if BLAS is in the toolchain

[ocaisa]

The logic for this is already used in https://github.com/easybuilders/easybuild-easyblocks/blob/develop/easybuild/easyblocks/s/superlu.py#L66

This logic is outdated though and should be updated to include FlexiBLAS and OpenBLAS (if the CMake version is recent enough)

[boegel]

See https://cmake.org/cmake/help/latest/module/FindBLAS.html .

Looks like it's not that trivial for imkl...

[ocaisa]

I think in the case of MKL we could accept that we can't do it, but in the other cases we should set it to force picking up the right library

[ocaisa]

Actually one way to address would be to use Intel10_64_dyn and let MKL decide what to do at runtime. This would probably mean changes in how we link to MKL though (which is already being used at JSC I think).