Supporting ROCm 1.7

[alexanderkjeldaas]

Issue description

This is a new release described in ROCm/ROCm#254

@emerth writes:

in a nutshell, install ROCm per instructions then install CUDA. You will still have to deal with getting
rid of nouveau - do that after installing ROCm.
I have this scheme running on an Ubuntu 16.04 box with an RX470 and a GTX970.

[alexanderkjeldaas]

This also requires the ROCK kernel. They will release a 4.13-based ROCK kernel though. See ROCm/ROCm#256

[alexanderkjeldaas]

https://github.com/RadeonOpenCompute/ROCK-Kernel-Driver

[ob7]

can we use rocm in nixos yet?
have u seen this yet: https://github.com/peter-sa/nixos-rocm ?