UCX network seems to be missing ROCm specific parts

[rbberger]

Code like the following https://github.com/StanfordLegion/legion/blob/master/runtime/realm/ucx/ucp_internal.cc#L266-L277 seem to indicate that the ROCm specific parts have not been implemented yet.

[lightsighter]

That is almost certainly the case since the UCX module was built by people at NVIDIA and has therefore not been tested on any AMD machines. Assigning @pmccormick for now to find someone who might be able to work on it.