dt-bindings: irq: mtk,sysirq: add support for MT8516

Add binding documentation of mediatek,sysirq for MT8516 SoC.
Signed-off-by: Fabien Parent <fparent@baylibre.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt

@@ -5,6 +5,7 @@ interrupt.
 
 Required properties:
 - compatible: should be
+	"mediatek,mt8516-sysirq", "mediatek,mt6577-sysirq": for MT8516
 	"mediatek,mt8183-sysirq", "mediatek,mt6577-sysirq": for MT8183
 	"mediatek,mt8173-sysirq", "mediatek,mt6577-sysirq": for MT8173
 	"mediatek,mt8135-sysirq", "mediatek,mt6577-sysirq": for MT8135