* add examples into grouped/batched_gemm
* adding splitK examples
* fixed splitK
* add bfp16 int8 example into splitK
* formatting
* use static_cast
* added common for batched_gemm
* add commons for examples of splitK/batched/grouped_gemm
* return true
* adjust splitK check tol
* update example
Co-authored-by: Chao Liu <lc.roy86@gmail.com>
