ARM: mvebu: switch to using gpiod API in pm-board code

This switches PM code to use the newer gpiod API instead of legacy
gpio API that we want to retire.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>