ramips: fix USB LED for Belkin F9K1109v1

ramips: fix USB LED for Belkin F9K1109v1

Device support for Belkin F9K1109v1 was added using set_usb_led()
although this was removed in 772b27c20736 ("ramips: set F5D8235 v1
usb led trigger via devicetree").

Use ucidef_set_led_usbport() instead.

Fixes: f2c83532f92c ("ramips: add support for Belkin F9K1109v1")
Signed-off-by: Sungbo Eo <mans0n@gorani.run>
[rephrase commit title and message, backport]
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
(cherry picked from commit 1f455418ef1ea67fda710e1b86a9e021bb4a2413)