cpu: Stop including arch/decoder.hh.

Stop including arch/decoder.hh, and fix up transitive includes.

Change-Id: I9ef2efd0ab427e17bea4382b89a097c17e619332
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/52081
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
9 files changed