ath79: increase max SPI clock for DIR-859 A1

Increase the spi-max frequency to 50 MHz, similar to the DIR-842.

Signed-off-by: Jan Forman <[email protected]>
[improve commit title, fix commit message alignment]
Signed-off-by: Adrian Schmutzler <[email protected]>

target/linux/ath79/dts/qca9563_dlink_dir-859-a1.dts

@@ -79,7 +79,7 @@
 	flash@0 {
 		compatible = "jedec,spi-nor";
 		reg = <0>;
-		spi-max-frequency = <30000000>;
+		spi-max-frequency = <50000000>;
 
 		partitions {
 			compatible = "fixed-partitions";