qmake-generated Makefiles since 4.6 (according to bug report) contain
recursive qmake invocations with absolute paths to .pro files, where the
absolute paths are not escaped.
Task-number: QTBUG-11776
Change-Id: I49772c7d9147efea3bb7b9623c61d92aa0bb6857
Reviewed-by: Jonas Gastal <jgastal@profusion.mobi>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>