[p2p] Small follow-ups to 21528

Summary:
Backport of core#22618.

Depends on D10933.

Ref T1693.

Test Plan:

ninja all check-all

Reviewers: #bitcoin_abc, tyler-smith, PiRK

Reviewed By: #bitcoin_abc, tyler-smith, PiRK

Subscribers: tyler-smith

Maniphest Tasks: T1693

Differential Revision: https://reviews.bitcoinabc.org/D10934