Add several symbol in the whitelist for exported symbols.

Summary: As far as I can tell, they shouldn't be exported teh way they are, but end up being on recent ubuntu/debian . While this great mystery is figured out, add them to the whitelist.

Test Plan: Do gitian build and ensure the symbol test phase checks out.

Reviewers: freetrader, Mengerian, #bitcoin_abc

Reviewed By: Mengerian, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D602