kernel: add kmod-leds-turris-omnia

kernel: add kmod-leds-turris-omnia

Add support for LEDs of the CZ.NIC Turris Omnia using the upstream
driver.

There is no generic way to control the LEDs in UCI manner, however
the kernel module is the first step to actually use the RGB LEDs in
custom logic.

Signed-off-by: Stefan Kalscheuer <stefan@stklcode.de>
(removed DMARC notice, added driver to Turris Omnia, moved module
recipe to target/linux/mvebu/modules.mk)
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
(cherry picked from commit f8fa38c13fcc3b4ce9a4dfc56d98e5188353afac)
Reviewed-by: Robert Marko <robimarko@gmail.com>