[dev-qt/qtgui:4] Cleanups.

Also, don't install qtconfig icon and desktop file if the app is not built.

Package-Manager: portage-2.2.10
[dev-qt/qtgui:4] Apply patch from Fedora to fix bug 491226.

Package-Manager: portage-2.2.10
[dev-qt/qtgui:4] Remove obsolete workaround.

IIRC these paths are added by cairo.pc when cairo is built
with USE=qt4. Since we've been depending on cairo[-qt4] for
a while now, this hack should no longer be needed.

Package-Manager: portage-2.2.10