configs,gpu-compute: Fixes to connect gmTokenPort

configs,gpu-compute: Fixes to connect gmTokenPort

When the TokenPort was moved from the GCN3 staging branch to develop the
TokenPort was changed from being the port connecting the ComputeUnit to
Ruby's vector memory port to a sideband port which inhibits requests to
Ruby's vector memory port. As such, it needs to be explicitly connected
as a new port. This changes the getPort method in ComputeUnit to be
aware of the port as well as modifying the example config to connect to
TCPs.

The iteration to connect in the config file was modified since it was
not properly connecting to TCPs each time and Ruby.py does not
explicitly return a list of each MachineType.

Change-Id: Ia70a6756b2af54d95e94d19bec5d8aadd3c2d5c0
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35096
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>