[TF-A] Changelog for v2.9 Release

Hello everyone,

Please take a look at the changelog for your respective platforms ahead of the TF-A v2.9 release. The changelog is autogenerated from the commit messages of the patches that have been merged since the v2.8 release. Here's your chance to give us guidance on any small manual adjustments you would like to see.

Patch: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/20975

Rendered Version: https://ci-builds.trustedfirmware.org/static-files/7aZOCOLylZ7jd48oTAPxMxyUT...

Thanks,

Juan Pablo