drm/i915/xe2lpd: implement WA for underruns while enabling FBC

drm/i915/xe2lpd: implement WA for underruns while enabling FBC

FIFO underruns are observed when FBC is enabled on plane 2 or
plane 3. Recommended WA is to update the FBC enabling sequence.
The plane binding register bits need to be updated separately
before programming the FBC enable bit.

Bspec: 74151
Reviewed-by: Mika Kahola <mika.kahola@intel.com> #v3
Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231111114320.87277-2-vinod.govindapillai@intel.com