cpu: convert tage_base to new style stats

Change-Id: If03102af545855125e87782c77ff5b43da8ac73b
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/33937
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
2 files changed