doc: remove redundant leds bindings

remove file doc/device-tree-bindings/leds/common.txt
as we have this now already in
dts/upstream/include/dt-bindings/leds/common.h
which is imported from linux.

Signed-off-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
1 file changed