README update

Author: ilg-ul

README.md

@@ -122,14 +122,13 @@ For more details please read the
 
 ### Versioning
 
-The version strings used by the GCC project are three number string
+The version strings used by the GCC project are three number strings
 like `11.3.0`; to this string the xPack distribution adds a four number,
-as the SiFive version,
 but since semver allows only three numbers, all additional ones can
 be added only as pre-release strings, separated by a dash,
-like `11.3.0-1`. The fifth number is the xPack release.
+like `11.3.0-1`.
 When published as a npm package, the version gets
-a sixth number, like `11.3.0-1.1`.
+a fifth number, like `11.3.0-1.1`.
 
 Since adherence of third party packages to semver is not guaranteed,
 it is recommended to use semver expressions like `^11.3.0` and `~11.3.0`