drm/i915: Remove duplicate intel_uncore_forcewake_reset.

Since early sanitize and uncore sanitize are called one after the other,
I think, we can remove second forcewake reset which was are calling
twice in both the functions.

Note that this is merge fallout between

commit ef46e0d2
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sat Nov 16 16:00:09 2013 +0100

    drm/i915: restore the early forcewake cleanup

and

commit 521198a2
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Fri Aug 23 16:52:30 2013 +0300

    drm/i915: sanitize forcewake registers on reset

Signed-off-by: Deepak S <deepak.s@intel.com>
[danvet: Explain how this came to be.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>