tests: eliminated usage of qttest_p4.prf

tests: eliminated usage of qttest_p4.prf

qttest_p4.prf was added as a convenience for Qt's own autotests in Qt4.
It enables various crufty undocumented magic, of dubious value.
Stop using it, and explicitly enable the things from it which we want.

Since QT+= had to be touched already, this change also removes a lot of
useless duplication on those lines.

Change-Id: I9f2f20eaf4a0e676beddf474c7db8680e4712f78
Reviewed-on: http://codereview.qt-project.org/6302
Sanity-Review: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Jason McDonald <jason.mcdonald@nokia.com>