MIPS: BCM47xx: Fix LEDs on WRT54GS V1.0

Reported-by: Catalin Patulea <cat@vv.carleton.ca>
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/7113/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>