libaom v3.1.1 Released

[Wan-Teh Chang]

Hello everyone,

libaom v3.1.1 has been released. The source code of the release can be
checked out from the git repository[1] using the release tag v3.1.1.
Alternatively, the release tarball[2], along with the signature file[3],
can be downloaded.

Thanks.

[1] https://aomedia.googlesource.com/aom
[2] https://storage.googleapis.com/aom-releases/libaom-3.1.1.tar.gz
[3] https://storage.googleapis.com/aom-releases/libaom-3.1.1.tar.gz.asc

This release includes several bug fixes.

- Bug fixes:
Issue 2965: Cherry-picked the following four commits for the
tune=butteraugli mode.
1. Add libjxl to pkg_config if enabled:
https://aomedia-review.googlesource.com/c/aom/+/136044
2. Declare set_mb_butteraugli_rdmult_scaling static:
https://aomedia-review.googlesource.com/c/aom/+/134506
3. Add color range detection in tune=butteraugli mode:
https://aomedia-review.googlesource.com/c/aom/+/135521
4. Enable tune=butteraugli in all-intra mode:
https://aomedia-review.googlesource.com/c/aom/+/136082

Issue 3021: Fix vmaf model initialization error when not set to
tune=vmaf

Issue 3050: Compilation fails with -DCONFIG_TUNE_VMAF=1

Issue 3054: Consistent crash on near-static screen content, keyframe
related