[OpenMP] Directly use user's grid and block size in kernel language mode (#70612)

In kernel language mode, use user's grid and blocks size directly. No
validity
check, which means if user's values are too large, the launch will fail,
similar
to what CUDA and HIP are doing right now.

GitOrigin-RevId: 3768039913be32666a316a2b5c12739c423dbc61
3 files changed