I am planning to orphan mingw-qt.
- it fails to build on F28, presumably due to the __debug_install_post
hook not generating the debugsource lists properly
- releng/Till complains that the build log is now 3Gbytes long (due to
more elaborate compiler diagnostics)
Fixing this is more work than I'm willing to do.
Furthermore, the last released version of 4.8 is 3 years old, and we
have qt5 in mingw. Keeping qt4 alive seems like more work than it's worth...