We didn't pass actually the targetMode and mkspec to qmake. E.g.
on Mac, debugging helpers therefore couldn't compile if the default
qmake mkspec is xcode.

Task-number: QTCREATORBUG-5806
Change-Id: I575012386983e1e285a500f99a34b7f21dcba29d
Reviewed-on: http://codereview.qt.nokia.com/2947


Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Eike Ziller <eike.ziller@nokia.com>