This is a minor Qt bump to drop a few patches. It also has some style changes.
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core#24668
> 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/fix_bigsur_style.patch
> * adjusted patches:
> - patches/qt/fix_limits_header.patch
>
> Co-authored-by: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
> build, qt: drop fix_no_printer.patch
>
> The removed patch is not required since switching Qt version from
> 5.12.11 to 5.15.2.
> build, qt: use one patch per line in depends/packages/qt.mk
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core#25719
> build: Bump Qt to 5.15.5 in depends
> qt: use patch over sed for guix CROSS_LIBRARY_PATH change
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This is a backport of core#24668 and core#25719
Depends on D13918