Tests: Remove insignificant marker for Win7 build with Angle

tst_controls is now passing for the Windows 7 32bit with Angle
configuration.

Task-number: QTBUG-33029
Change-Id: If0b47b827d97bb654a12bb8a2c9dc98d3b968988
Reviewed-by: Sergio Ahumada <sahumada@blackberry.com>