[dev-qt/qtcore:4] Remove redundant code.

We always run qmake with CONFIG+=nostrip, so these lines are unnecessary.

Package-Manager: portage-2.2.10
[dev-qt/qtcore:4] Split translations into dev-qt/qttranslations.
[qt4-build-multilib.eclass] Get rid of install_directories().
[Qt4] Handle installation of private headers in qt4-build-multilib.eclass
[qt4-build-multilib.eclass] Improve and rename qt_mkspecs_dir().
[qt4-build-multilib.eclass] No need to define PLATFORM.

We already pass the mkspec to configure via "-platform <foo>",
which should have the same effect.