Integrate SonicMoE kernels

[hemildesai]

https://github.com/Dao-AILab/sonic-moe/

1. The current API can only be used without EP, so integrate it for non EP paths.

2. Investigate whether a grouped gemm from sonicmoe could be used with EP. The grouped gemm function would need to implement the following for best perf:

• gemm_gated followed by router weight multiplication in the down projection gemm epilogue similar to gemm_dgated
• Custom backward for the two gemms
  Constraints:
  Tokens are already permuted for EP so only need the grouped gemm portion from sonic moe, but that API is not yet available.

[hemildesai]

Update: Dao-AILab/sonic-moe#9

Use this for EP