drm/i915: drop redundant vblank waits

Just blows through 50ms for naught, since the pipe is off.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -4733,8 +4733,6 @@ static int i9xx_crtc_mode_set(struct drm_crtc *crtc,
 
 	i9xx_set_pipeconf(intel_crtc);
 
-	intel_wait_for_vblank(dev, pipe);
-
 	I915_WRITE(DSPCNTR(plane), dspcntr);
 	POSTING_READ(DSPCNTR(plane));
 
@@ -5704,8 +5702,6 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
 
 	ironlake_set_pipeconf(crtc, adjusted_mode, dither);
 
-	intel_wait_for_vblank(dev, pipe);
-
 	/* Set up the display plane register */
 	I915_WRITE(DSPCNTR(plane), DISPPLANE_GAMMA_ENABLE);
 	POSTING_READ(DSPCNTR(plane));