Enable huc on DG2

The huc doens't work on xe driver. I tried to change "i915.enable_guc=2 to xe.enable_guc=2" in cmdline, but it doesn’t work. Is the HUC loaded and enabled on XE? If not, please help to enable it. Thanks.

(Lucas) Re-purposing this issue: it's now enabled on all platforms but DG2