[backport#13756] wallet: avoid reuse flags

Summary:
Add m_avoid_address_reuse flag to coin control object.
Add avoid_reuse wallet flag and accompanying strings/caveats.

https://github.com/bitcoin/bitcoin/pull/13756/commits/eec15662fad917b169f5e3b8baaf4301dcf00a7b

Depends on D6369

Partial backport of Core PR13756

Test Plan:

ninja

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D6370