The UBSan raises a division by zero in getRadialGradientValues. This can
be avoided by calculating the inverse in
qt_fetch_radial_gradient_template as a checker is done to avoid
division by zero there. (Credit to OSS-Fuzz)
Pick-to: 6.7
Fixes: QTBUG-120332
Change-Id: I798d1efc87ee07df7ca6f401aa476013cdbffe42
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>