tools: get the latest config.guess/config.sub and patch to support arm64_32
It's updated independently from automake which we use to pick a recent enough version.
The fake automake path is to fool the contribs in using that one prioritarily.
v2:
Tell autoreconf to use our config.guess/sub rather than its own in contribs and VLC. We may not need update_config
when RECONF is used. But in some cases we may not need RECONF at all.
Edited by Steve Lhomme