alternatively ... and more elegant ... you can build that device-tree from kernel sources - e.g. download a 5.x.y kernel from kernel.org (I tested if with linux-5.10.6 ), unpack it and enter the source directory ( cd linux-5.10.6 in my case )
This is the diff which I got from the kernel developer
diff --git a/arch/arm/boot/dts/imx6qdl-sr-som.dtsi b/arch/arm/boot/dts/imx6qdl-sr-som.dtsi
index b06577808ff4..3db08363d3fb 100644
--- a/arch/arm/boot/dts/imx6qdl-sr-som.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-sr-som.dtsi
@@ -53,7 +53,6 @@
&fec {
pinctrl-names = "default