ARM: dts: armada388-clearfog: move device specific pinctrl nodes

Move the device specific pinctrl nodes over to use the label form to
reference the pin mux controller, rather than replicating the device
node path.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>