ROG Ally X missing audio on SteamOS 3.7 without linux-firmware-20241017 or cherry-picking

[matte-schwartz]

Your system information

• Steam client version: N/A
• SteamOS version: SteamOS 3.7 Staging w/ linux-neptune-611 and linux-firmware-neptune-jupiter.20241205.1
• Opted into Steam client beta?: Yes
• Opted into SteamOS beta?: Yes
• Have you checked for updates in Settings > System?: Yes

Please describe your issue in as much detail as possible:

Audio:

The ROG Ally has working audio on SteamOS Main and SteamOS Staging without any further work necessary. The ROG Ally X, however, needs upstream linux-firmware-20241017: https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/commit/?h=20241017&id=4cbaca8d279c5b37dc999e9e6b9a5d8c3cbad2f5 and https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/commit/?h=20241017&id=e1bd5010f8403734ff9e2fc02b1f9477c3665142. There is also one kernel patch that correctly identifies the internal amplifier hardware: https://lore.kernel.org/lkml/[email protected]/T/ that adds some additional audio clarity.

I saw that linux-firmware-neptune was tagged with a 20241205.1 tag, but it doesn't look like it's picked up upstream linux-firmware within that tag.