DEVICETREE: Misc fix for the AR7100 SPI controller binding

Fix the clocks property documentation and use lower case for
hex values in the example.

Signed-off-by: Alban Bedel <[e-mail]>
Signed-off-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/spi/spi-ath79.txt

···
 Required properties:
 - compatible: has to be "qca,<soc-type>-spi", "qca,ar7100-spi" as fallback.
 - reg: Base address and size of the controllers memory area
-- clocks: phandle to the AHB clock.
+- clocks: phandle of the AHB clock.
 - clock-names: has to be "ahb".
 - #address-cells: <1>, as required by generic SPI binding.
 - #size-cells: <0>, also as required by generic SPI binding.
···
 
 Example:
 
-	spi@1F000000 {
+	spi@1f000000 {
 		compatible = "qca,ar9132-spi", "qca,ar7100-spi";
-		reg = <0x1F000000 0x10>;
+		reg = <0x1f000000 0x10>;
 
 		clocks = <&pll 2>;
 		clock-names = "ahb";