Properties list for Xen

Some functions and macros are found to have properties relevant to the Xen codebase. For this reason, the file docs/properties.json contains all the needed properties.

Here is an example of the properties.json file:

   "version": "1.0",
   "content": [
         "description": ""
         "type": "function",       // required
         "value:": "^printk*.$",   // required
            "pointee_write": "1..2=never",
            "pointee_read": "",
            "taken": ""
            "attribute": ""

Here is an explanation of the fields inside an object of the "content" array: