add device config env for the accelerator (#5396)
Thank you for [pr](https://github.com/microsoft/DeepSpeed/pull/5369) and
@delock contribution of ideas.
As mentioned in this
[pr](https://github.com/microsoft/DeepSpeed/pull/5369), each device has
its own environmental variables.
We create visible_devices_envs() and set_visible_devices_envs() methods
on the accelerator class to enable each accelerator to implement env
settings within the interface , which is more generic to other
accelerators.
this commit has tested on npu, each one has 8 ascend npus
---------
Co-authored-by: yangcheng <yangcheng104@huawei.com>
Co-authored-by: eigen2017 <wobushiliu2@gmail.com>
Co-authored-by: Logan Adams <114770087+loadams@users.noreply.github.com>
Co-authored-by: Olatunji Ruwase <olruwase@microsoft.com>
