drm/i915: Silence sparse over duplicate members in static initializer

drivers/gpu/drm/i915/i915_drv.c|100 col 18| warning: Initializer entry defined twice
drivers/gpu/drm/i915/i915_drv.c|101 col 3| also defined here
drivers/gpu/drm/i915/i915_drv.c|117 col 18| warning: Initializer entry defined twice
drivers/gpu/drm/i915/i915_drv.c|118 col 3| also defined here

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>