cpu: Add a branch_prediction namespace

Encapsulate all branch-prediction-related files
in a branch_prediction namespace. This will allow
these files to be renamed to drop the BP suffix.

Issued-on: https://gem5.atlassian.net/browse/GEM5-982
Change-Id: I640c0caa846a3aade6fae95e9a93e4318ae9fca0
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47303
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
47 files changed