mem-ruby: Update port names in Ruby

mem-ruby: Update port names in Ruby

After the terminology update commit there were still many confusing
names in the Ruby ports. This changeset is a proposal for updating these
names.

For an example use case, see the following resources changeset.
https://gem5-review.googlesource.com/c/public/gem5-resources/+/34416

Change-Id: I01d4f24a70b300e39438ee147dfab7a8d674d5c7
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/34417
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>