ARM: dts: Kirkwood: Fix QNAP TS219 power-off

The "reg" entry in the "poweroff" section of "kirkwood-ts219.dtsi"
addressed the wrong uart (0 = console). This patch changes the address
to select uart 1, which is the uart connected to the pic
microcontroller, which can switch the device off.

Signed-off-by: Helmut Klein <hgkr.klein@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Fixes: 4350a47b

 ("ARM: Kirkwood: Make use of the QNAP Power off driver.")
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>