Adds support for Corsair Hydro H100i RGB Pro XT

I have this cooler in my server. I added this change to enable liquidctl to work on my Proxmox server. The fans on the H100i were running at 85% pretty much all the time. After adding, i was able to add a fan curve that dropped the fan speeds down considerably to 49%:

~$ sudo /opt/liquidctl-venv/bin/liquidctl status
Corsair Hydro H100i RGB PRO XT
├── Liquid temperature 29.4 °C
├── Fan 1 speed 1363 rpm
├── Fan 1 duty 49 %
├── Fan 2 speed 1320 rpm
├── Fan 2 duty 49 %
├── Pump speed 2420 rpm
└── Pump duty 75 %

Other Information:
USB vendor/product ID: 1b1c:0c2d
Firmware version: 2.0.9
I think this AIO cooler has 16 total fan LEDS but I don't remember, I used to have it in a desktop years ago. Since they're in a server now they're inactive.

If the implementation is not trivial, please also include a short overview.

Fixes:
Closes:
Related: #442

Checklist:

• Adhere to the development process
• Conform to the style guide
• Verify that the changes work as expected on real hardware
• Add automated tests cases
• Verify that all (other) automated tests (still) pass
• Update/add documentation
  • README, with "new/changed in" notes
  • applicable docs/*guide.md device guides, with "new/changed in" notes
  • liquidctl.8 Linux/Unix/Mac OS man page
  • protocol documentation in docs/developer/protocol
• Submit relevant data, scripts or dissectors to https://github.com/liquidctl/collected-device-data

New CLI flag?

• Adjust the completion scripts in extra/completions/

New device?

• Regenerate extra/linux/71-liquidctl.rules (instructions in the file header)
• Add entry to the README's supported device list with applicable notes and git MRLV

New driver?

• Document the protocol in docs/developer/protocol/