X11+EGL on Vibrante Linux fails to build out of the box

The DRIVE CX supports eglfs (DRM+EGLDevice), wayland, and X11 as well.

X11 (xcb+EGL) has not been tested and is reported not to build out of the box, mainly because WIN_INTERFACE_CUSTOM which leads to the non-X11 EGL typedefs (good for eglfs and wayland, not so much for xcb).

Note: Unrelated to Qt, but the X11 headers in current Vibrante have to be patched a bit. Patch for include/X11/extensions/Xge.h attached. include/xcb/* are missing but can simply be copied from a normal distro. After these configuring with -qt-xcb succeeds (but still with EGL on X disabled).