asahi: G14X fixes
Turns out G14X finally made a breaking change: the CDM header has an extra 2 words tacked on after it.
It also doesn't need the G13X coherency stuff, that looks like it was a one-off hack/workaround.
Kernel side in the usual branch, no breaking changes.
Draft until I validate that the CDM change isn't configurable/showed up on G14G on 13.5.
Edited by Asahi Lina