ARM: mvebu: Add clock properties to Armada XP timer node

With the addition of the Armada XP reference clock, we can now model
accurately the available clock inputs for the timer: namely, nbclk
and refclk. For each of this clock inputs we assign a name, for the
driver to select as appropriate.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

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

@@ -70,6 +70,8 @@ serial@12300 {
 
 			timer@20300 {
 				compatible = "marvell,armada-xp-timer";
+				clocks = <&coreclk 2>, <&refclk>;
+				clock-names = "nbclk", "fixed";
 			};
 
 			coreclk: mvebu-sar@18230 {