On platforms like the Raspberry Pi the EGL implementation is not
compatible with X. This means that while EGL and Open GL ES can be enabled,
and will work fine with platform plugins like eglfs, EGL (and thus GL) should
be automatically disabled in xcb, otherwise a compilation error will occur
since xcb assumes the native handle types are the corresponding Xlib types.
Task-number: QTBUG-36551
Change-Id: I2cc4c558abb4b25d422a2c01da9b75b865ace402
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>