Android: Add -DQT_OPENGL_FORCE_SHADER_DEFINES to configure

In order to make Qt Quick 2 app run on an emulator, we need
to define QT_OPENGL_FORCE_SHADER_DEFINES in the build.

Task-number: QTBUG-32576
Change-Id: I4bd3d34db94bb993cac668d70d66407ef1662311
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>