egl/x11: Support DRI3 v1.1

egl/x11: Support DRI3 v1.1

Add support for DRI3 v1.1, which allows pixmaps to be backed by
multi-planar buffers, or those with format modifiers. This is both
for allocating render buffers, as well as EGLImage imports from a
native pixmap (EGL_NATIVE_PIXMAP_KHR).

Signed-off-by: Louis-Francis Ratté-Boulianne <lfrb@collabora.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>