dns/unbound: Update 1.24.2 => 1.25.0

While here, drop backported patch, it's in upstream now.

News:
https://www.nlnetlabs.nl/news/2026/Apr/29/unbound-1.25.0-released/
Changelog:
https://nlnetlabs.nl/projects/unbound/download/#unbound-1-25-0

PR: 294931
Reported by: Herbert J. Skuhra <herbert@gojira.at>
Approved by: Jaap Akkerhuis <jaap@NLnetLabs.nl> (maintainer)
Approved by: vvd (co-mentor)
MFH: 2026Q2