ramips: cudy wr1300v2 reduce SPI freq to 40000000

Cases have been reported in which certain devices do not boot correctly
or have errors. After various tests by users who have such errors it has
been concluded that the SPI frequency should be reduced to 40Mhz, at
this speed it appears that all devices work correctly.

Signed-off-by: Óscar García Amor <[email protected]>

target/linux/ramips/dts/mt7621_cudy_wr1300-v2.dts

@@ -58,8 +58,7 @@
 	flash@0 {
 		compatible = "jedec,spi-nor";
 		reg = <0>;
-		spi-max-frequency = <80000000>;
-		m25p,fast-read;
+		spi-max-frequency = <40000000>;
 
 		partitions {
 			compatible = "fixed-partitions";