ARM: dts: armada-xp: add interrupts for watchdog

The first interrupt is for the regular watchdog timeout. Normally the
RSTOUT line will trigger a reset before this interrupt fires but on
systems with a non-standard reset it may still trigger.

The second interrupt is for a timer1 which is used as a pre-timeout for
the watchdog.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>