Handle Hermitian matrix product in gemm_core() function (faust_linear_algebra)...

Handle Hermitian matrix product in gemm_core() function (faust_linear_algebra) and use it in Palm4MSA(FFT) algos.

- Before: we had 'T' for transpose matrix and 'N' normal matrix. Now: we have the additional 'H' for transconjugate matrix.
- This is not yet handled when using gemm BLAS computation (it's only for eigen and it raises an exception if using BLAS with 'H').
- This is for handling more properly Palm4MSA matrix complex approximation.
- Palm4MSA is modified, optimized and clarified by using this new capability.