libvpx Wigeon Duck v1.15.1-rc1

[Jerome Jiang]

Hello,

Wigeon Duck v1.15.1 has been tagged[1]. Please help testing and report issues[2].
This release bumped up the SO major version that was missing in the v1.15.0 release.

Thanks.

[1]https://chromium.googlesource.com/webm/libvpx/+/refs/tags/v1.15.1-rc1
[2]https://g-issues.webmproject.org/issues/new?pli=1&authuser=0&component=1615215&template=2023762

Changelog:

2025-01-09 v1.15.1 "Wigeon Duck"
  This release bumps up the SO major version and fixes the language about ABI
  compatibility in the previous release changelog.