drm/i915: Kill RMW from ILK reset code

All the other bits in the GDSR register are read-only, so we don't have
to preserve them when we perform a GPU reset.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --cc drivers/gpu/drm/i915/intel_uncore.c
Simple merge