linux-v4l2: Add additional Extension Unit controls

[ggodlewski]

Description

It allows controlling Logitech BRIO and Kiyo Pro FOV and other settings

https://www.kernel.org/doc/html/v4.10/media/v4l-drivers/uvcvideo.html#extension-unit-xu-support

Motivation and Context

Normal V4L2 controls do not allow to change FOV and HDR settings for Logitech Brio and Kiyo Pro.

How Has This Been Tested?

Tested with Logitech BRIO. FOV change works.

Looking for tester who owns Kiyo Pro. The constants were copied from https://github.com/soyersoyer/cameractrls so in theory it should work.

Looking for someone with FreeBSD to test. Maybe it should be turned off for this OS?

Types of changes

New feature (non-breaking change which adds functionality)

Checklist:

• [x] My code has been run through clang-format.
• [x] I have read the contributing document.
• [x] My code is not on the master branch.
• [ ] The code has been tested.
• [x] All commit messages are properly formatted and commits squashed where appropriate.
• [x] I have included updates to all appropriate documentation.

[keriszafir]

Got a Kiyo Pro, willing to test.

[emaste]

I've got a Kyio Pro and will try to give it a test on FreeBSD at some point.