Add GPU Support to ZKRust

[MauroToscano]

[PatStiles]

Referencing: yetanotherco/zkRust#20 (comment) . Risc0 is currently failing due to a toolchain issue. Specifically installing using cargo risczero appears to not install riscv32-unknown-elf-gcc. I made an issue in there discord https://discord.com/channels/953703904086994974/1291124782049267825.