ramips: fix cpuclock for the GB-PC1

The GnuBee PC1 stock bootloader runs at 900Mhz. This fixes bad clock drift when running the platform.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

target/linux/ramips/dts/GB-PC1.dts

@@ -102,6 +102,11 @@
 	};
 };
 
+&cpuclock {
+	compatible = "fixed-clock";
+	clock-frequency = <90000000>;
+};
+
 &pcie {
 	status = "okay";
 };