arch-x86, mem: Add support for PCID to x86

This change adds Process Context Identifier (PCID) support
to x86, so that tlb entries can be tagged using pcid.

Change-Id: I695eccc4b08476b32d4b3728fc3c42b2ad6f5a28
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35835
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
4 files changed