Check Minimal if regardless of SegWit.

Summary: Right now nothing is using it, and separation of concerns dictate that we don't want this tied to segwit.

Test Plan:

make check
../qa/pull-tester/rpc-tests.py

Reviewers: freetrader, #bitcoin_abc

Reviewed By: freetrader, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D60