txorphanage: Extract HaveOrphanTx

Summary:
Extract some common code into HaveOrphanTx function.

This is a backport of core#21148 [5/14]
https://github.com/bitcoin/bitcoin/pull/21148/commits/83679ffc600305ec0926fd195ee31c11de2ed613

Depends on D11484

Test Plan:
With clang and debug:
ninja all check-all

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Subscribers: Fabien

Differential Revision: https://reviews.bitcoinabc.org/D11485