egl/dri2: Dispatch eglCreateImageKHR by display, not driver

Add dri2_egl_display_vtbl::create_image, set it for each platform, and
let egl_dri2 dispatch eglCreateImageKHR to that.

To remove ambiguity, rename egl_dri2.c:dri2_create_image() to
dri2_create_image_from_dri().

This prepares for the EGL platform extensions.

Signed-off-by: Chad Versace <chad.versace@linux.intel.com>
6 files changed