[electrum] also use patched btchip-python in non-deterministic requirements-hw.txt

Summary:
This is also needed if we want pip install -r ... to work with recent pip versions.
Dedup some comments and specify the library name in the deterministic requirements file.

Depends on D17796

Test Plan: pip install -r contrib/requirements/requirements-hw.txt

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D17797