leds: spi-byte: Use devm_led_classdev_register_ext()

Use extended classdev registration to generate generic device names from
color and function enums instead of reading only the label from the
device tree.

Signed-off-by: Stefan Kalscheuer <stefan@stklcode.de>
Link: https://lore.kernel.org/r/20240204150726.29783-1-stefan@stklcode.de


Signed-off-by: Lee Jones <lee@kernel.org>