ARM: imx: dts: Use lower case for bindings notation

Improve the DTS files using lower case to fix the following dtc warnings:

Warning (simple_bus_reg): Node /XXX@<UPPER> simple-bus unit address format error, expected "<lower>"

Converted using the following command:

find . -type f \( -iname *.dts -o -iname *.dtsi \) -exec sed -i -e "s/@\([0-9a-fA-FxX\.;:#]+\)\s*{/@\L\1 {/g" -e "s/@0x\(.*\) {/@\1 {/g" -e "s/@0+\(.*\) {/@\1 {/g" {} +^C

For simplicity, two sed expressions were used to solve each warnings separately.

To make the regex expression more robust a few other issues were resolved,
namely setting unit-address to lower case, and adding a whitespace before the
the opening curly brace:

https://elinux.org/Device_Tree_Linux#Linux_conventions

This is a follow up to commit 4c9847b7 ("dt-bindings: Remove leading 0x from bindings notation")
Reported-by: David Daney <ddaney@caviumnetworks.com>
Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6q-display5.dtsi

@@ -255,7 +255,7 @@ &i2c1 {
 	pinctrl-0 = <&pinctrl_i2c1>;
 	status = "okay";
 
-	codec: tfa9879@6C {
+	codec: tfa9879@6c {
 		#sound-dai-cells = <0>;
 		compatible = "nxp,tfa9879";
 		reg = <0x6C>;