arm64: zynqmp: Add u-boot,dm-pre-reloc to clk300 node

This node is used by qspi driver for supporting qspi boot mode in SPL.

Similar changes have beeen done by commit a9022b017a90
("ARM64: zynqmp: Add u-boot,dm-pre-reloc to clk nodes")

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/arm/dts/zynqmp-clk.dtsi b/arch/arm/dts/zynqmp-clk.dtsi
index a795efd..c70f85a 100644
--- a/arch/arm/dts/zynqmp-clk.dtsi
+++ b/arch/arm/dts/zynqmp-clk.dtsi
@@ -38,6 +38,7 @@
 		compatible = "fixed-clock";
 		#clock-cells = <0>;
 		clock-frequency = <300000000>;
+		u-boot,dm-pre-reloc;
 	};
 
 	clk600: clk600 {