rtw88: re-connect to the build

This adds the (updated) rtw88 driver back to the build.
Functionality has not been tested (much) so might not currently
work but people offered to test.

Firmware is provided by the wifi-firmware-rtw88-kmod port/package.

This reverts commit 712468443df1130db8f893a5e2ce5c6a8dbf5cde.