Fix perf-top crash on imx6qsabrelite

http://www.spinics.net/lists/arm-kernel/msg225176.html

Signed-off-by: Liviu Gheorghisan <liviu.gheorghisan@enea.com>
---
diff --git a/arch/arm/boot/dts/imx6q.dtsi b/arch/arm/boot/dts/imx6q.dtsi
index 5806312..9540094 100644
--- a/arch/arm/boot/dts/imx6q.dtsi
+++ b/arch/arm/boot/dts/imx6q.dtsi
@@ -144,6 +144,10 @@
 			status = "disabled";
 		};
 
+		pmu {
+			compatible = "arm, cortex-a9-pmu";
+			interrupts = <0 94 0x04>;
+		};
 
 		aips-bus@02000000 { /* AIPS1 */
 			spba-bus@02000000 {