Since moving `_connect_things` to a pre-init step, the ArmBoard can now be refactored to set up things in a more logical manner. In particular, this patch moves activity out of the `_add_disk_to_board` function and into the `_pre_initialization` function. Change-Id: I5d40267f28ae87cd483a0396739c09b8b2b46383 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/65052 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu> Maintainer: Bobby Bruce <bbruce@ucdavis.edu>