- Fix the build on GCC-based architectures, e.g. PowerPC[64]
- Drop no longer relevant CONFLICTS_INSTALL with Qt4 version
- Don't remove -Wno-unused-result flag from CXXFLAGS: it was added as part of r363837 back in 2014 to appease a certain compiler version (I forgot which one), but today it is not needed anymore on any supported FreeBSD version
PR: 237255
Submitted by: Piotr Kubaj