ARCv2: [axs103] bump CPU frequency from 75 to 90 MHZ

With up-to-date FPGA builds ARC cores are supposed to correctly operate
even with 90 MHz clock (which is a target frequency for AXS103 release).
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: arc-linux-dev@synopsys.com

arch/arc/boot/dts/axc003.dtsi

@@ -12,7 +12,7 @@
 
 / {
 	compatible = "snps,arc";
-	clock-frequency = <75000000>;
+	clock-frequency = <90000000>;
 	#address-cells = <1>;
 	#size-cells = <1>;
 

arch/arc/boot/dts/axc003_idu.dtsi

@@ -12,7 +12,7 @@
 
 / {
 	compatible = "snps,arc";
-	clock-frequency = <75000000>;
+	clock-frequency = <90000000>;
 	#address-cells = <1>;
 	#size-cells = <1>;