ARM: shmobile: marzen-reference: Set SMSC lan to use irq-push-pull

This change makes the DTS consistent with the platform data
that exists in board-marzen.c.

Empirically it does not appear to be necessary.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7779-marzen-reference.dts

@@ -45,6 +45,7 @@ lan0@18000000 {
 		phy-mode = "mii";
 		interrupt-parent = <&irqpin0>;
 		interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
+		smsc,irq-push-pull;
 		reg-io-width = <4>;
 		vddvario-supply = <&fixedregulator3v3>;
 		vdd33a-supply = <&fixedregulator3v3>;