ARM: dt: Add binding for Tegra PMC

The Tegra PMC (Power Management Controller) interfaces with an external
PMU (Power Management Unit), and controls wake-up from sleep modes.

This initial binding is the bare minimum required to control the PMC's
inversion of the PMU's interrupt signal.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
diff --git a/arch/arm/boot/dts/tegra-harmony.dts b/arch/arm/boot/dts/tegra-harmony.dts
index 9a52615..6e8447d 100644
--- a/arch/arm/boot/dts/tegra-harmony.dts
+++ b/arch/arm/boot/dts/tegra-harmony.dts
@@ -10,6 +10,10 @@
 		reg = < 0x00000000 0x40000000 >;
 	};
 
+	pmc@7000f400 {
+		nvidia,invert-interrupt;
+	};
+
 	i2c@7000c000 {
 		clock-frequency = <400000>;