[net processing] Move Misbehaving() to PeerManager

Summary:
Completes backport (9/9) of core PR19791:
https://github.com/bitcoin/bitcoin/pull/19791/commits/bb6a32ce9983c72afa90f41a43a47ffd703ca006

Depends on D9048.

Also moves the other Misbehaving() prototype (specific to our
codebase) as a private method.

Test Plan:

ninja all check-all

Reviewers: #bitcoin_abc, majcosta

Reviewed By: #bitcoin_abc, majcosta

Subscribers: majcosta

Differential Revision: https://reviews.bitcoinabc.org/D9049