The container node of the leds has never had the name gpio_leds,
so there is no regression here, it just never worked.
Instead of fixing it, just drop it.

Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>