ARM: i.MX5 clocks: Remove optional clock setup (CKIH1) from i.MX51 template

External high frequency clock CKIH1 is optional for i.MX51, so move
it setup into boards where it is used.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
diff --git a/arch/arm/boot/dts/imx51.dtsi b/arch/arm/boot/dts/imx51.dtsi
index d7b0646..f0b25c9 100644
--- a/arch/arm/boot/dts/imx51.dtsi
+++ b/arch/arm/boot/dts/imx51.dtsi
@@ -47,7 +47,7 @@
 
 		ckih1 {
 			compatible = "fsl,imx-ckih1", "fixed-clock";
-			clock-frequency = <22579200>;
+			clock-frequency = <0>;
 		};
 
 		ckih2 {