Update OnePlus 6 packages and kernel

This MR updates the OnePlus 6 and 6T with the following changes:

SDM845 (OnePlus 6 + PocoPhone F1)

• Update kernel to v5.12.8
• Add kernel side support for the audio hardware in the OnePlus 6 (enchilada)

Both devices

• Disable kernel logging to the framebuffer, enable the UART console instead.
• Add a missing dependency to make sure the GPU firmware is included in the initramfs. This fixes osk-sdl

OnePlus 6 (enchilada)

• Update SDM845 alsa UCM fork to include configs for the OnePlus 6 (enchilada)
• The headphone jack and speaker on the OnePlus 6 are now both fully functional!

Unfortunately, the OnePlus 6T uses a different speaker which is currently missing driver support. It also doesn't have a headphone jack, as a result audio is still broken on this device.

Currently debugging an issue where sometimes the soc-qcom-sdm845-nonfree-firmware package postinstall script doesn't get executed, resulting in wifi not working on device (until the services are manually enabled and started). I'll remove the draft prefix when it's resolved and when the kernel is tested on beryllium.

Cc: @sdm845-mainline