Multi-Scalar Multiplication for the Grumpkin curve cycle

[!NOTE] This is basically a copy of the pasta_msm crate.

To compile CUDA support ensure that you have nvcc, Nvidia CUDA compiler, on your program search path. Minimal installation suffices. For example on Ubuntu it would be sufficient to install cuda-minimal-build-11-7 instead of complete cuda package. If your laptop is equipped with a Turing+ controller, you're likely to have to compile with --features=cuda-mobile. Caveat lector. CUDA implementation does not adapt for the actual load yet, so that some results would be suboptimal.