drm/i915: Read the CCK fuse register from CCK

drm/i915: Read the CCK fuse register from CCK

When reading a CCK register we should obviously read it from CCK not
Punit. This problem has been present ever since this of code was
introduced in

 commit ee4af34cd6cb0dee121a16fc5b5f17afa8f3d0b2
 Author: Deepak S <deepak.s@linux.intel.com>
 Date:   Thu Jul 10 13:16:24 2014 +0530

    drm/i915: populate mem_freq/cz_clock for chv

The problem was raised during review by Mika [1] but somehow slipped
through the cracks, and the patch got applied with the problem unfixed.

[1] http://lists.freedesktop.org/archives/intel-gfx/2014-July/048937.html

Cc: Deepak S <deepak.s@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>