The FFmpeg building flow has become too different on linux and macos.
Decoupling the logic makes it more simple to follow.
The CR also fixes nits and shellcheck warnings in install-ffmpeg.
Pick-to: 6.8
Change-Id: I28639d28c7210809e52ff18ce612da52f8754285
Reviewed-by: Jøger Hansegård <joger.hansegard@qt.io>
(cherry picked from commit 39ad0317d1)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
On qtci-macos-13-x86_64 host CI tries to build and run the test on
Android (arm64) while we still haven't managed to install FFmpeg for it.
The same situation happened with qtci-linux-RHEL-8.8-x86_64 and Android
x86.
Task-number: QTBUG-110805
Task-number: QTBUG-114954
Task-number: QTBUG-113980
Pick-to: 6.6 6.5
Change-Id: If953221b104d5bb8fce9d48f8ecd977c2e80c41d
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>