[TF-A] Changelog for v2.15 Release

Hello Everyone,

Ahead of the TF-A v2.15 release, please review the autogenerated changelog for your platform. It’s built from the commit messages of all patches merged since v2.15.

If you spot anything that needs a quick manual tweak, just let us know.

Patch: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/51064

Rendered Version: https://ci-artifacts.trustedfirmware.org/static-files/kCIohqhXYMnQJYSWz3aUfd...

-- Thanks, Harrison