configs: Specify cache, dir, and mem cntrl interleaving

configs: Specify cache, dir, and mem cntrl interleaving

This changeset allows setting a variable for interleaving.
That value is used together with the number of directories to
calculate numa_high_bit, which is in turn used to set up
cache, directory, and memory controller interleaving.
A similar approach is used to set xor_low_bit, and calculate
xor_high_bit for address hashing.

Change-Id: Ia342c77c59ca2e3438db218b5c399c3373618320
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28134
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>