Update ffmpeg version to 5.1 for desktop platforms

Some issues have been fixed in ffmpeg 5.1, e.g, with videotoolbox.
So the update at least fixes our playback
of some video formats on macos, e.g. provided in the related bug.

After the update I tested the basic functionality on windows,
linux, macOS, and run CI tests, which are OK.

Task-number: QTBUG-98102
Change-Id: I72f45780e1c3983d6a1941db2b833b78784b90de
Reviewed-by: Samuel Mira <samuel.mira@qt.io>
Reviewed-by: Lars Knoll <lars@knoll.priv.no>
(cherry picked from commit 0f8eccdfc5)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

coin/provisioning/common/unix/install-ffmpeg.sh

@@ -68,9 +68,9 @@ version="f0d2ed135c3602670b56a95e0346487730317407"
 url_public="https://github.com/FFmpeg/FFmpeg/archive/$version.tar.gz"
 sha1="a429060d07b6d84c849a68741f816a7e91447d12"
 else
-version="n5.0"
+version="n5.1"
 url_public="https://github.com/FFmpeg/FFmpeg/archive/refs/tags/$version.tar.gz"
-sha1="1a979876463fd81e481d53ceb3cc117f0fce8521"
+sha1="1d4283c5ff9e02378893168f55b8672bb30b9176"
 fi
 
 url_cached="http://ci-files01-hki.intra.qt.io/input/ffmpeg/$version.tar.gz"

coin/provisioning/common/windows/install-ffmpeg.ps1

@@ -42,9 +42,9 @@
 # This script will install FFmpeg
 $msys = "C:\Utils\msys64\usr\bin\bash"
 
-$version = "n5.0"
+$version = "n5.1"
 $ffmpeg_name = "ffmpeg-" + $version;
-$sha1 = "3F7C6D5264A04BC27BA471D189B0483954820D65"
+$sha1 = "9D5AD63032B03922D38F99159728F24C305FC345"
 
 $url_cached = "http://ci-files01-hki.intra.qt.io/input/ffmpeg/" + $version + ".zip"
 $url_public = "https://github.com/FFmpeg/FFmpeg/archive/refs/tags/" +$version + ".zip"