drm/i915/gen9: Add WaInPlaceDecompressionHang

Add this workaround to prevent hang when in place compression
is used.

References: HSD#2135774
Cc: stable@vger.kernel.org
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
(cherry picked from commit 4ba9c1f7)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>