[backport#16129] Include core_io.h from core_read.cpp
Summary:
https://github.com/bitcoin/bitcoin/pull/16129/commits/67f4e9c52270f9ddf8f7e83f0906af5e6743b33a
Concludes backport of Core PR16129
Test Plan:
ninja check
Reviewers: #bitcoin_abc, deadalnix
Reviewed By: #bitcoin_abc, deadalnix
Differential Revision: https://reviews.bitcoinabc.org/D6331