GH-43: Update ZW_classcmd.h to latest version

This is a merge between e3d5b1838531a916132034fb943eb01db19cfdec that is latest stable version of the file and the latest one from u3c branch

Bug-SiliconLabs: UIC-3222
Bug-GitHub: #43
Signed-off-by: Philippe Coval <[email protected]>

Author: silabs-borisl