clk: fixed-factor: Fix device-tree binding typo

The required properties are not named "div" and "mult",
but rather "clock-div" and "clock-mult".
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

Documentation/devicetree/bindings/clock/fixed-factor-clock.txt

@@ -19,6 +19,6 @@ Example:
 		compatible = "fixed-factor-clock";
 		clocks = <&parentclk>;
 		#clock-cells = <0>;
-		div = <2>;
-		mult = <1>;
+		clock-div = <2>;
+		clock-mult = <1>;
 	};