ARM: dts: exynos: Add missing interrupts property to PMIC on Trats board

PMIC node requires external interrupts for proper operation, but property
defining them was missing. This was probably caused by a limited support
for interrupts from more than one parent, which was not possible to define
when support for this board was added. Fix this by adding
'interrupt-extended' property and properly define interrupt lines for PMIC
node.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>