[][mt7981: remove spi dummy clk node]

[Description]
Remove spi dummy clk node for mt7981

[Release-log]
N/A

Change-Id: Ia3ac7676a90a52f63d028dd260dace714cee1264
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/5336913
diff --git a/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7981.dtsi b/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7981.dtsi
index b1e44ea..eebd1eb 100644
--- a/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7981.dtsi
+++ b/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7981.dtsi
@@ -182,12 +182,6 @@
 		#clock-cells = <0>;
 	};
 
-	spi_clk: dummy_spi_clk {
-		compatible = "fixed-clock";
-		clock-frequency = <208000000>;
-		#clock-cells = <0>;
-	};
-
 	timer {
 		compatible = "arm,armv8-timer";
 		interrupt-parent = <&gic>;