CONTRIBUTING.md: Add bindings&software version guidelines

To ensure consistency with software, add guidelines on how to use the
semantic versioning information. The first release should have major
version at least 1. The dt-binding compatible must be suffixed by
-v<major>.

Signed-off-by: Jorge Marques <[email protected]>

Author: gastmaier

CONTRIBUTING.md

@@ -139,7 +139,25 @@ and responsibilities that he or she has by using them.
 - If it's the case, to update all the README files of the affected projects
   and IP cores.
 
-Resources:
+## Devicetree bindings & drivers
+
+The IPs typically follow [Semantic Versioning 2.0.0](https://semver.org/)
+and his information must be used in devicetree bindings and drivers to assert
+compatibility. The first stable release version should be higher or equal to
+v1.0.0 and all fields should be treated as decimals.
+
+Devicetree compatibles take the major number prefixed by **v**, for example,
+the **compatible** of *axi_my_ip* v1.2.3 is **adi,axi-my-ip-v1** and the
+**dt-binding** filename is **adi,axi-my-ip.yaml** (no major suffix). Per the
+last paragraph, *adi,axi-my-ip-v0* is **never** appropriate.
+
+Software drivers must parse the **VERSION** register for feature handling
+across versions. The patch number shouldn't have to be handled by software
+drivers, if it seems necessary to, consider incrementing the minor number
+instead.
+
+## Related resources
+
 * [How to write a good commit message](https://cbea.ms/git-commit/) and [another resource](https://gist.github.com/rsp/057481db4dbd999bb7077f211f53f212)
 * [Write better commits, build better projects](https://github.blog/2022-06-30-write-better-commits-build-better-projects/)
 * [Good commit example (but extreme one)](https://dhwthompson.com/2019/my-favourite-git-commit)