drm/i915: ring w/a initialisation for gen 9

Add framework for gen 9 HW WAs

v1: Changed SOC specific WA function to gen 9 common function (Req: Damien Lespiau)

Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
1 file changed