Consider adding support for PyTorch on Apple M1/M2 MPS enabled devices

[dazzag24]

PyTorch now runs on Apple M1 MPS devices. This could open up access to MONAI to a wider range of users without the need for a dedicated GPU device.

However the current support for MPS is not 100% complete so this is very likely not feasible right now.

Others have already run into operations that are not supported e.g Conv3D() and the PyTorch team have stated that they are planning on adding support.

See this which tracks adding support for the missing operations for the MPS backend.

[wyli]

looks like github ci runners don't currently support setup-python with these devices https://github.blog/changelog/2022-08-09-github-actions-self-hosted-runners-now-support-apple-m1-hardware/