ARM: Tegra: Add clock entry for smp_twd clock

As DT support for clocks and smp_twd is enabled, add clock entry
for smp_twd clock to DT.

This fixes the following error while booting the kernel:
smp_twd: clock not found -2
Signed-off-by: Prashant Gaikwad <pgaikwad@nvidia.com>
[swarren: include kernel log spew that this fixes]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/boot/dts/tegra20.dtsi

@@ -118,6 +118,7 @@ timer@50004600 {
 		compatible = "arm,cortex-a9-twd-timer";
 		reg = <0x50040600 0x20>;
 		interrupts = <1 13 0x304>;
+		clocks = <&tegra_car 132>;
 	};
 
 	intc: interrupt-controller {

arch/arm/boot/dts/tegra30.dtsi

@@ -119,6 +119,7 @@ timer@50004600 {
 		compatible = "arm,cortex-a9-twd-timer";
 		reg = <0x50040600 0x20>;
 		interrupts = <1 13 0xf04>;
+		clocks = <&tegra_car 214>;
 	};
 
 	intc: interrupt-controller {