ARM: dts: Enable UART wake-up events for beagleboard

For device tree based booting, we need to use wake-up
interrupts like we already do for some omaps. This fixes
a PM regression on beagleboard compared to legacy booting.
Tested-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/omap3-beagle.dts

@@ -292,6 +292,7 @@ &twl_gpio {
 &uart3 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart3_pins>;
+	interrupts-extended = <&intc 74 &omap3_pmx_core OMAP3_UART3_RX>;
 };
 
 &gpio1 {