a7fbe68535
Added a RCCL_MSCCL_ENABLE_DONE_EVENT env var, set it be 0 by default.
The env var is to control whether to use doneEvent when invoking MSCCL
kernels.
Skipping doneEvent would cause the firmware to skip L2 cache flush,
resulting in overall performance improvement.
[ROCm/rccl commit: 12dba425de]