docs: dt-bindings: Document preferred line wrapping

There are some patches with long lines as a result of checkpatch
enforcing 100, not 80, but checkpatch is only a tool not a coding style.
The Linux Kernel Coding Style is still clear here on preferred limit.
Mentioned preferred style of wrapping long lines in DTS, based on Linux
Kernel Coding Style.

Signed-off-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[email protected]>

Author: krzk

Documentation/devicetree/bindings/dts-coding-style.rst

@@ -162,21 +162,27 @@ Example::
 		status = "okay";
 	}
 
-Indentation
------------
+Indentation and wrapping
+------------------------
 
-1. Use indentation according to Documentation/process/coding-style.rst.
+1. Use indentation and wrap lines according to
+   Documentation/process/coding-style.rst.
 2. Each entry in arrays with multiple cells, e.g. "reg" with two IO addresses,
    shall be enclosed in <>.
-3. For arrays spanning across lines, it is preferred to align the continued
-   entries with opening < from the first line.
+3. For arrays spanning across lines, it is preferred to split on item boundary
+   and align the continued entries with opening < from the first line.
+   Usually avoid splitting individual items unless they significantly exceed
+   line wrap limit.
 
 Example::
 
 	thermal-sensor@c271000 {
 		compatible = "qcom,sm8550-tsens", "qcom,tsens-v2";
 		reg = <0x0 0x0c271000 0x0 0x1000>,
 		      <0x0 0x0c222000 0x0 0x1000>;
+		/* Lines exceeding coding style line wrap limit: */
+		interconnects = <&aggre1_noc MASTER_USB3_0 0 &mc_virt SLAVE_EBI1 0>,
+				<&gem_noc MASTER_APPSS_PROC 0 &config_noc SLAVE_USB3_0 0>;
 	};
 
 Organizing DTSI and DTS