Prepare for CUDA Python new documentation layout

[leofang]

https://github.com/rapidsai/rmm/blob/1024a1250cfde7e93d26dc6d5e063e84c4a39824/python/rmm/docs/conf.py#L200

Once this PR https://github.com/NVIDIA/cuda-python/pull/183 is merged I expect that RMM doc build will break again.

Based on this search team RMM is the only consumer of CUDA Python's objects.inv, so wanted to inform you in advance 🙂

[leofang]

Our docs has been rebuilt last Friday, so the new URL should be replaced to https://nvidia.github.io/cuda-python/cuda-bindings/. This file can be inspected:

$ python -m sphinx.ext.intersphinx https://nvidia.github.io/cuda-python/cuda-bindings/objects.inv | grep cudaCpuDeviceId
    cuda.bindings.runtime.cudaCpuDeviceId                                            : module/runtime.html#cuda.bindings.runtime.cudaCpuDeviceId

[leofang]

(If https://nvidia.github.io/cuda-python/cuda-bindings/ does not work for any reason, I would like to know and we should also try https://nvidia.github.io/cuda-python/cuda-bindings/latest...)