[media-kit] media-libs/libavif doesn't compile

Nobody has claimed this yet.

```
Calculating dependencies... done!
[ebuild N ] media-libs/libavif-1.2.1::media-kit USE="aom dav1d gdk-pixbuf rav1e -examples -extras" 13,618 KiB

Total: 1 package (1 new), Size of downloads: 13,618 KiB
>>> Verifying ebuild manifests
>>> Emerging (1 of 1) media-libs/libavif-1.2.1::media-kit
>>> Failed to emerge media-libs/libavif-1.2.1, Log file:
>>> '/var/tmp/portage/media-libs/libavif-1.2.1/temp/build.log'
>>> Jobs: 0 of 1 complete, 1 failed Load avg: 0.37, 0.09, 0.26
* Package: media-libs/libavif-1.2.1
* Repository: media-kit
* USE: amd64 aom dav1d elibc_glibc gdk-pixbuf kernel_linux rav1e userland_GNU
* FEATURES: preserve-libs userpriv
>>> Unpacking source...
>>> Unpacking libavif-1.2.1.tar.gz to /var/tmp/portage/media-libs/libavif-1.2.1/work
/var/tmp/portage/media-libs/libavif-1.2.1/work /var/tmp/portage/media-libs/libavif-1.2.1/work
/var/tmp/portage/media-libs/libavif-1.2.1/work
>>> Source unpacked in /var/tmp/portage/media-libs/libavif-1.2.1/work
>>> Preparing source in /var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1 ...
* Working in BUILD_DIR: "/var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1_build"
>>> Source prepared.
>>> Configuring source in /var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1 ...
* Working in BUILD_DIR: "/var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1_build"
cmake -C /var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1_build/gentoo_common_config.cmake -G Ninja -DCMAKE_INSTALL_PREFIX=/usr -DBUILD_SHARED_LIBS=ON -DAVIF_CODEC_AOM=ON -DAVIF_CODEC_DAV1D=ON -DAVIF_CODEC_LIBGAV1=OFF -DAVIF_LOCAL_ZLIBPNG=OFF -DAVIF_LOCAL_JPEG=OFF -DAVIF_BUILD_GDK_PIXBUF=ON -DAVIF_ENABLE_WERROR=OFF -DAVIF_CODEC_RAV1E=ON -DAVIF_CODEC_SVT=OFF -DAVIF_BUILD_EXAMPLES=OFF -DAVIF_BUILD_APPS=OFF -DAVIF_BUILD_TESTS=OFF -DCMAKE_BUILD_TYPE=Gentoo -DCMAKE_TOOLCHAIN_FILE=/var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1_build/gentoo_toolchain.cmake /var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1
CMake Warning:
Ignoring empty string ("") provided on the command line.

loading initial cache file /var/tmp/portage/media-libs/libavif-1.2.1/work/libavif-1.2.1_build/gentoo_common_config.cmake
-- The C compiler identification is GNU 12.3.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/x86_64-pc-linux-gnu-gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Found PkgConfig: /usr/bin/x86_64-pc-linux-gnu-pkg-config (found version "2.2.0")
-- Checking for module 'libyuv'
-- Package 'libyuv' not found
CMake Error at CMakeLists.txt:194 (message):
Cannot find libyuv. Make sure it's installed on the system, or pass
-DAVIF_LIBYUV=LOCAL (to fetch and build it locally) or -DAVIF_LIBYUV=OFF
(to disable it)
Call Stack (most recent call first):
CMakeLists.txt:217 (check_avif_option)
```

It seems that the tree is without `libyuv` package. We can choice to disable statically that option or add the package `libyuv`.

Start with the libavif CMakeLists.txt checks at lines 194 and 217 and review the ebuild configuration that enables the aom, dav1d, gdk-pixbuf, and rav1e USE flags. Confirm whether the repository should provide libyuv or disable AVIF_LIBYUV, then verify that media-libs/libavif-1.2.1 configures and builds successfully.

Written by the indexing model from the issue text.