ARM: mvebu: add SSCG to Armada 370 Device Tree

The Armada 370 SoC has a Spread Spectrum Clock Generator. This commit
adds the description of this generator to the Device Tree describing
this SoC.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Leigh Brown <leigh@solinno.co.uk>
Link: https://lkml.kernel.org/r/1409645719-20003-4-git-send-email-gregory.clement@free-electrons.comSigned-off-by: Jason Cooper <jason@lakedaemon.net>

arch/arm/boot/dts/armada-370.dtsi

@@ -225,6 +225,10 @@ thermal@18300 {
 				status = "okay";
 			};
 
+			sscg@18330 {
+				reg = <0x18330 0x4>;
+			};
+
 			interrupt-controller@20000 {
 				reg = <0x20a00 0x1d0>, <0x21870 0x58>;
 			};