feat(surface-arm64-audio): Qualcomm LPASS/Q6DSP audio for Surface Laptop 7

[foil-copy-overrate]

Surface Laptop 7 Audio DSP support (Snapdragon X Elite)

Adds Qualcomm LPASS/Q6DSP audio support on top of the base surface-arm64 image.

Audio path on x1e80100

YubiOS userspace
    → WirePlumber (policy: 91-surface-arm64-qcom.lua)
        → PipeWire
            → ALSA UCM (x1e80100/HiFi profile)
                → snd_soc_sc8280xp (kernel driver, upstream since 6.11)
                    → Q6 DSP (firmware via linux-firmware, loaded over QRTR)
                        → LPASS codec → speaker / headphone / DP audio

New files (contrib/surface/arm64/)

File	Purpose
Containerfile.fedora	Adds alsa-utils, alsa-ucm-conf, pipewire, wireplumber
usr/lib/modprobe.d/surface-arm64-audio.conf	snd_soc_sc8280xp + Q6ASM module options
usr/share/wireplumber/main.lua.d/91-surface-arm64-qcom.lua	Q6DSP routing policy
usr/share/alsa/ucm2/UCM-NOTES.md	Documents UCM status + how to get x1e80100 profiles

Known state

• Upstream alsa-ucm-conf does not yet ship x1e80100 profiles; UCM-NOTES.md documents the workaround
• snd_soc_sc8280xp driver is in upstream kernel since 6.11; Fedora rawhide kernel includes it
• Speaker/headphone output functional with correct UCM; microphone path untested
• DP audio works via USB4 snd_soc_hdmi_codec (Surface Laptop 7 uses USB4 for display)

Depends on

• Base surface-arm64 PR contrib/surface: add Surface Laptop 7 arm64/Snapdragon X Elite bootc example (upstream kernel, NX Mode SB workaround) #2 must be merged first (qrtr + pd-mapper must already be running)

References

• https://patchwork.kernel.org/project/alsa-devel/list/?q=x1e80100+audio
• Surface Laptop 7th Edition Support linux-surface/linux-surface#1590