Add udev rule to notify systemd of available framebuffer
Using psplash in combination with systemd the splash screen is not
shown. The dependency to sys-devices-platform-gpu-graphics-fb0.device
will terminate psplash-start.service because systemd is not aware of the
existing framebuffer device node.
See https://lists.yoctoproject.org/g/yocto/topic/91286438#57156
Signed-off-by: Bastian Wanner <bastian.wanner@inovex.de>
