linux-imx

drm/i915: simplify i915_reset a bit

- need_display is always true, scrap it.
- don't reacquire the mutex to do nothing after having restored the
  gem state.

Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>