173ef8980d921c9c0e46257747ab1165965e3ced build: Small libxcb.mk improvements (Hennadii Stepanov)
5129b36573cb07d8bcbac493506c46e26d7239eb build: Clean remnants of QTBUG-34748 fix (Hennadii Stepanov)
Pull request description:
Hope, this PR will make [transit](https://github.com/bitcoin/bitcoin/pull/21376) to Qt 5.12.10 neater.
A fix for [QTBUG-34748](https://bugreports.qt.io/browse/QTBUG-34748) was introduced in #5915 (v0.11.0, Qt 5.2.1).
[QTBUG-34748](https://bugreports.qt.io/browse/QTBUG-34748) was [fixed](b19b080894) in Qt 5.3.0.
The separated [`fix-xcb-include-order.patch`](bb44d9e754/depends/patches/qt/fix-xcb-include-order.patch), provided by #5915, was dropped in #12971 while bumping Qt to 5.9.4 (5.9.6). But `libxcb.mk` remained unchanged.
This PR reverts #5915 for `libxcb.mk` as well.
ACKs for top commit:
practicalswift:
cr ACK 173ef8980d921c9c0e46257747ab1165965e3ced: patch looks correct
fanquake:
ACK 173ef8980d921c9c0e46257747ab1165965e3ced
Tree-SHA512: 9815a7e532ff4aa08f9623ded8d5708eca1c9c73ac7a2684419a18c125da7627b44ac3191f2e7978946942c8d0580e73b1a93df624986fb2a13791a68ce1e025