ARM: dts: DRA7: wdt: Fix compatible property for watchdog node

OMAP wdt driver supports only ti,omap3-wdt compatible. In DRA7 dt
wdt compatible property is defined as ti,omap4-wdt by mistake instead of
ti,omap3-wdt. Correcting the typo.

Fixes: 6e58b8f1 ("ARM: dts: DRA7: Add the dts files for dra7 SoC and dra7-evm board")
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/dra7.dtsi

@@ -653,7 +653,7 @@ timer16: timer@4882e000 {
 		};
 
 		wdt2: wdt@4ae14000 {
-			compatible = "ti,omap4-wdt";
+			compatible = "ti,omap3-wdt";
 			reg = <0x4ae14000 0x80>;
 			interrupts = <GIC_SPI 75 IRQ_TYPE_LEVEL_HIGH>;
 			ti,hwmods = "wd_timer2";