build, qt: bump Qt5 version to 5.15.3
Qt 5.15.3 release is a patch release made on the top of Qt 5.15.2. As a patch release, Qt 5.15.3 does not add any new functionality but provides bug fixes and other improvements.
https://code.qt.io/cgit/qt/qtreleasenotes.git/about/qt/5.15.3/release-note.md
- dropped patches:
- patches/qt/dont_use_avx_android_x86_64.patch
- patches/qt/fix_bigsur_style.patch
- adjusted patches:
- patches/qt/fix_android_jni_static.patch
- patches/qt/fix_limits_header.patch
- patches/qt/use_android_ndk23.patch




