Add CDC parsing host test

[tore-espressif]

This is a refactor that separates Descriptor parsing logic to a separate file with its own private API.

This new private API is than used with newly added USB mock, so we can test the parsing logic on Linux host tests.

There is a number of hardcoded USB descriptors of tested and verified CDC devices that must work with this driver.

TODO:

• [x] 4G modems are not yet added. (follow-up MR?) EDIT: 4 modems added

[tore-espressif]

Thank you for the review @roma-jam , I'll address the comments ASAP