QmlProfiler: Add qt4projectmanager dependency also in plugins.pro

Make sure qt4projectmanager is built before qmlprofiler gets linked.

Change-Id: I34efcdd431c18b5941e0748213fec0b8e80d1600
Reviewed-on: http://codereview.qt.nokia.com/469


Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@nokia.com>