drm/i915: Kill the dev variable in intel_suspend_complete()

The macros we use there are the magic ones that can take either dev or
dev_priv. We'd like to move as much as possible towards dev_priv though.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>