drm/i915: Remove stale comment from __intel_set_mode()

Since the following commit, the PLL calculations are done earlier, so
the code following the comment doesn't do anything PLL or encoder
related. It only updates the primary plane now.

commit f3019a4d
Author: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Date:   Wed Oct 29 11:32:37 2014 +0200

    drm/i915: Remove crtc_mode_set() hook
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -11723,9 +11723,6 @@ static int __intel_set_mode(struct drm_crtc *crtc,
 
 	modeset_update_crtc_power_domains(state);
 
-	/* Set up the DPLL and any encoders state that needs to adjust or depend
-	 * on the DPLL.
-	 */
 	for_each_intel_crtc_masked(dev, modeset_pipes, intel_crtc) {
 		struct drm_plane *primary = intel_crtc->base.primary;
 		int vdisplay, hdisplay;