DisplayPort via USB Type-C does not work on roc-rk3399-pc with Linux 5.19.17 and 6.0.7

[shvetsnikita]

Hello!

Like in u-boot issue, DP via Type-C support does not work in libretech-linux too, with both of upstream u-boot and u-boot builds from libretech-u-boot repo.

[shvetsnikita]

I verified that Display Port works via USB Type-C with Ubuntu 18.04 image I downloaded from Firefly a couple of years ago, so hardware is fine, but something missing in the kernel or/and DeviceTree.

[shvetsnikita]

Also could be related to #14