[MOVEONLY] Move cpuid code from random & sha256 to compat/cpuid

Summary:
Partial backport of core PR17270:
https://github.com/bitcoin/bitcoin/pull/17270/commits/723c79666770b30cce9f962bed5ece8cc7d74580

Test Plan:

ninja all check-all

Run the Gitian builds.

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D6161