Fix behavior with FLUIDFFT_TRANSONIC_BACKEND + allow things like "pythran+numba+cython"
We now have FLUIDFFT_TRANSONIC_BACKEND
for build time. But I don't think it really works :-)
We now have FLUIDFFT_TRANSONIC_BACKEND
for build time. But I don't think it really works :-)
Note that this now works for fluidsim, which is compiled for three Transonic backends: python, numba and pythran. So this will be easy to do the same for fluidfft once we use Meson.