dts: rk3368: make timer0 accessible for SPL and TPL

To use it with the DM timer driver in SPL and TPL, timer0 needs to be
marked as pre-reloc.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/dts/rk3368.dtsi b/arch/arm/dts/rk3368.dtsi
index 22fb7e7..b4f4f61 100644
--- a/arch/arm/dts/rk3368.dtsi
+++ b/arch/arm/dts/rk3368.dtsi
@@ -687,7 +687,7 @@
 		status = "disabled";
 	};
 
-	timer@ff810000 {
+	timer0: timer@ff810000 {
 		compatible = "rockchip,rk3368-timer", "rockchip,rk3288-timer";
 		reg = <0x0 0xff810000 0x0 0x20>;
 		interrupts = <GIC_SPI 66 IRQ_TYPE_LEVEL_HIGH>;