ARM: dts: i.MX27: Increase "clock-latency" value

i.MX27 CPU can be clocked with a 32 kHz quartz, and not just 32768 Hz,
so increase "clock-latency" value, which will ensure that we use two
clock cycles on frequency change.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

arch/arm/boot/dts/imx27.dtsi

@@ -61,7 +61,7 @@ cpu: cpu@0 {
 				266000 1300000
 				399000 1450000
 			>;
-			clock-latency = <61036>; /* two CLK32 periods */
+			clock-latency = <62500>;
 			clocks = <&clks 18>;
 			clock-names = "cpu";
 			voltage-tolerance = <5>;