drm/i915: use cpu_transcoder for TRANS_DDI_FUNC_CTL

... inside haswell_get_pipe_config. Because there's one TRANS_DDI_FUNC_CTL
register per CPU transcoder, not per pipe. This solves "unclaimed register"
messages when booting with eDP only and using the i915.disable_power_well=1.

Also fix a comment and remove an useless empty line.

The error messages were caused by:

  commit 88adfff1
  Author: Daniel Vetter <daniel.vetter@ffwll.ch>
  Date:   Thu Mar 28 10:42:01 2013 +0100
      drm/i915: hw readout support for ->has_pch_encoders
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -5990,16 +5990,15 @@ static bool haswell_get_pipe_config(struct intel_crtc *crtc,
 		return false;
 
 	/*
-	 * aswell has only FDI/PCH transcoder A. It is which is connected to
+	 * Haswell has only FDI/PCH transcoder A. It is which is connected to
 	 * DDI E. So just check whether this pipe is wired to DDI E and whether
 	 * the PCH transcoder is on.
 	 */
-	tmp = I915_READ(TRANS_DDI_FUNC_CTL(crtc->pipe));
+	tmp = I915_READ(TRANS_DDI_FUNC_CTL(cpu_transcoder));
 	if ((tmp & TRANS_DDI_PORT_MASK) == TRANS_DDI_SELECT_PORT(PORT_E) &&
 	    I915_READ(TRANSCONF(PIPE_A)) & TRANS_ENABLE)
 		pipe_config->has_pch_encoder = true;
 
-
 	return true;
 }