drm/i915: Keep intel_drv.h tidy

Something already got misplaced (although it's from a patch from
before Paulo's cleanup). Move it to the right spot.

v2: Remove the line to keep a neat block, requested by Paulo.

Reported-by: Paulo Zanoni <przanoni@gmail.com>
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Paulo Zanoni <przanoni@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>