Exclude file list for xen scripts

Different Xen scripts can perform operations on the codebase to check its compliance for a set of rules, however Xen contains some files that are taken from other projects (e.g. linux) and they can't be updated to ease backporting fixes from their source, for this reason the file docs/misra/exclude-list.json is kept as a source of all these files that are external to the Xen project.

Every entry of the file can be linked to different checkers, so that this list can be used by multiple scripts selecting only the required entries.

Here is an example of the exclude-list.json file:

|    "version": "1.0",
|    "content": [
|        {
|            "rel_path": "relative/path/from/xen/file",
|            "comment": "This file is originated from ...",
|            "checkers": "xen-analysis"
|        },
|        {
|            "rel_path": "relative/path/from/xen/folder/*",
|            "comment": "This folder is a library",
|            "checkers": "xen-analysis some-checker"
|        },
|        {
|            "rel_path": "relative/path/from/xen/mem*.c",
|            "comment": "memcpy.c, memory.c and memcmp.c are from the outside"
|        }
|    ]
Here is an explanation of the fields inside an object of the "content" array:

To ease the review and the modifications of the entries, they shall be listed in alphabetical order referring to the rel_path field. Excluded folder paths shall end with /* in order to match everything on that folder.