cpu: Added the Multiperspective Perceptron Predictor (8KB and 64KB)

Described by the following article:
Jiménez, D. "Multiperspective perceptron predictor."
Championship Branch Prediction (CBP-5) (2016).

Change-Id: Iaa68ead7696e0b6ba05b4417d0322e8053e10d30
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/15495
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Ilias Vougioukas <ilias.vougioukas@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>