linux-postmarketos-qcom-sm6125: upgrade to 6.0 (MR 3699)

This is a version bump for the sm6125 mainline kernel fork. It should
also fix a config issue.

Changes:
* Made QUSB2 built-in instead of a module (Fixes USB connectivity
issues)
* Updates to xiaomi-laurel device tree to fit new schema
* Changed maintainer name

Signed-off-by: Lux Aliaga <they@mint.lgbt>