drm/i915: Drop the nop intel_update_watermarks() call from haswell_crtc_enable()

HSW+ all use the .initial_watermarks() hook, so there's no point in
calling intel_update_watermarks() from HSW+ specific code. We'll still
hang on to the .initial_watermarks NULL check since theoretically if the
memory latencies are not populated we would not populate the function
pointer either.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480354637-14209-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>

drivers/gpu/drm/i915/intel_display.c

@@ -5465,10 +5465,7 @@ static void haswell_crtc_enable(struct intel_crtc_state *pipe_config,
 		intel_ddi_enable_transcoder_func(crtc);
 
 	if (dev_priv->display.initial_watermarks != NULL)
-		dev_priv->display.initial_watermarks(old_intel_state,
-						     pipe_config);
-	else
-		intel_update_watermarks(intel_crtc);
+		dev_priv->display.initial_watermarks(old_intel_state, pipe_config);
 
 	/* XXX: Do the pipe assertions at the right place for BXT DSI. */
 	if (!transcoder_is_dsi(cpu_transcoder))