ARM: dts: orion5x: gpio pin fixes for linkstation lswtgl

Here're a few gpio pin related fixes:
  - remove pinctrl-0 definition from pinctrl, since those pins are used
    in other places such as gpio-fan and regulators.
  - keep initial state of power led
  - fix for alarm pin of gpio-fan.

Fixes: dc57844a

 ("ARM: dts: orion5x: add buffalo linkstation ls-wtgl")
Signed-off-by: Roger Shimizu <rogershimizu@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>