ARM: dts: add buffalo linkstation ls-wvl/vl

Add dts file to support Buffalo Linkstation LS-WVL and LS-VL,
which are 3.5" HDD NAS in 2-bay and 1-bay respectively.

[gregory.clement@free-electrons.com: fix typo in pmx-led-function-red]
Signed-off-by: Roger Shimizu <rogershimizu@gmail.com>
Reviewed-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>