Blender Git Loki

Fix CPU rendering and OptiX denoiser in Cycles X

Make sure copying of temporary render buffers to the device
happens as part of the denoiser queue.

Initially thought this will be fixed by some more global changes
related to multi-GPU support, but:

- It is a simple and clear change.
- It brings multi-device support to a working state, which makes
it easier to verify changes.
- Multi-device is supported at a higher level, and it could still
be useful to support current usecases of DeviceDenoiser (where
input render buffers are allocated on a different device).

Differential Revision: https://developer.blender.org/D11742