egl_dri2: add a note about dri2_create_screen

The function is not called by platform_drm. As such one needs to
pay special attention at teardown.

v2: Fix the comment block. Spotted by Ken.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-and-tested-by: Kenneth Graunke <kenneth@whitecape.org> (v1)
1 file changed