learning-gem5: convert simple cache to new style stats

Change-Id: I6988c45c13955825fde974f390460f4473af017a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/34135
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