ARM: dts: exynos: Add interrupt line to MAX8997 PMIC on exynos4210-trats

MAX8997 PMIC requires interrupt and fails probing without it.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Fixes: d105f0b1 ("ARM: dts: Add basic dts file for Samsung Trats board")
Cc: <stable@vger.kernel.org>
[k.kozlowski: Write commit message, add CC-stable]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>