h8300: fix IRQ no

Old timer handler use 24 (Compare match A).
But current timer handler use 26 (Overflow).
Signed-off-by: NYoshinori Sato <ysato@users.sourceforge.jp>

arch/h8300/boot/dts/h8300h_sim.dts

@@ -73,7 +73,7 @@
 	timer16: timer@ffff68 {
 		compatible = "renesas,16bit-timer";
 		reg = <0xffff68 8>, <0xffff60 8>;
-		interrupts = <24 0>;
+		interrupts = <26 0>;
 		renesas,channel = <0>;
 		clocks = <&fclk>;
 		clock-names = "fck";