dts: sparx5: Enable ptp interrupt

Add support for ptp interrupt. This interrupt is used when using 2-step
timestamping. For each timestamp that is added in a queue, an interrupt
is generated.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/arm64/boot/dts/microchip/sparx5.dtsi

@@ -471,9 +471,10 @@ switch: switch@0x600000000 {
 				<0x6 0x10004000 0x7fc000>,
 				<0x6 0x11010000 0xaf0000>;
 			reg-names = "cpu", "dev", "gcb";
-			interrupt-names = "xtr", "fdma";
+			interrupt-names = "xtr", "fdma", "ptp";
 			interrupts =	<GIC_SPI 30 IRQ_TYPE_LEVEL_HIGH>,
-					<GIC_SPI 25 IRQ_TYPE_LEVEL_HIGH>;
+					<GIC_SPI 25 IRQ_TYPE_LEVEL_HIGH>,
+					<GIC_SPI 27 IRQ_TYPE_LEVEL_HIGH>;
 			resets = <&reset 0>;
 			reset-names = "switch";
 		};