This is a full revert of 59c859d6:
    drm/i915: account for only one PCH receiver on Haswell

Now that the PCH code is fixed to be able use the only PCH transcoder
independently of the pipe and CPU transcoder, we can revert this.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
[danvet: Resolve conflict due to the rebasing of dinq on top of
drm-next.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>