ucm2: sof-rt5682: add support for SOF rt5682 Chromebooks

[GitHub pull_request - opened <github@alsa-project.org>]

alsa-project/alsa-ucm-conf pull request #832 was opened from samson1357924:

## Summary

Add UCM configuration for the `sof-rt5682` sound card used on ChromeOS devices (Dratini/hatch family and others).

The configuration includes:

- `ucm2/conf.d/sof-rt5682/` - card UCM with HiFi profile, rt5682 headset/init sequences
- `ucm2/platforms/intel-sof/` - platform detection (DMI-based, glk/cml/tgl/jsl/adl/mtl) and codec probing helpers
- `ucm2/codecs/` - speaker amp and headset codec support files (max98357a, max98360a, max98373, max98390, rt1011, rt1015, rt1015p, rt1019p, rt5682s)
- `ucm2/codecs/hda/hdmi234.conf` - HDMI device helpers (reuses the existing `hdmi.conf` macro)

## Why

ChromeOS Chromebooks using the SOF driver with the `sof-rt5682` machine driver currently have **no audio** on Linux distributions without a UCM configuration: ACP/PipeWire cannot build a usable profile (only the "off" profile is available) and the system ends up with a Dummy Output. This affects at minimum the HP Pro C640 (Dratini), the Acer Chromebook Spin 513 (Dalboz) and several other hatch-family devices.

This was previously reported at https://github.com/WeirdTreeThing/chromebook-linux-audio/issues/265 (dummy output on LTS userspace) and discussed in PipeWire MR !2946.

## Testing

Verified on an **HP Pro C640 Chromebook** (Dratini, `Google_Hatch`, Intel Comet Lake) running Ubuntu 26.04 LTS:

- alsa-lib 1.2.15.3 (UCM syntax 7)
- kernel 7.0.0-29-generic (Ubuntu official), SOF firmware 2:2:0-57864
- pipewire 1.6.2 / wireplumber 0.5.13

Result: HiFi profile available and active, internal speakers (PCM 5), headphone jack (PCM 0, auto-switch works), DMIC capture and HDMI 1/2/3 all working. No Dummy Output, no WirePlumber errors.

All files are byte-identical to the standalone branch of WeirdTreeThing/alsa-ucm-conf-cros (verified via md5).

The UCM validator CI should cover the syntax; no alsa-info hardware emulation was added since the current `ucm-validator2` used by CI performs static verification.

Request URL   : https://github.com/alsa-project/alsa-ucm-conf/pull/832
Patch URL     : https://github.com/alsa-project/alsa-ucm-conf/pull/832.patch
Repository URL: https://github.com/alsa-project/alsa-ucm-conf