Qt installer needs to only show LGPL3 as option for open source Android package

The default binary build of Qt for Android port will only support LGPL3 or commercial licensing. For the community version, we should only show the LGPL3 license text and not suggest LGPL2 as an option. The reason for this is that the Android platform plugin will contain code licensed under Apache which is not compatible with LGPL2.

Note that it's possible to build Qt from source with the LGPL2 license as an option, but this will not be the default and we will not supply binary builds with this option.