arm64: tegra: Mark architected timer as always on

The architected timer on Tegra186 and Tegra194 is in an always on power
partition and its reference clock will always run, so mark the timer as
always on.
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra186.dtsi

@@ -1360,5 +1360,6 @@ timer {
 			     <GIC_PPI 10
 				(GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
 		interrupt-parent = <&gic>;
+		always-on;
 	};
 };

arch/arm64/boot/dts/nvidia/tegra194.dtsi

@@ -1053,5 +1053,6 @@ timer {
 			     <GIC_PPI 10
 				(GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
 		interrupt-parent = <&gic>;
+		always-on;
 	};
 };