drm/i915: Grab the pixel clock from adjusted_mode not requested_mode

i9xx_set_pipeconf() attempts to get the current pixel clock from
requested_mode. requested_mode.clock may be totally bogus, so the
clock should come from adjusted_mode.

v2: Dropped the intel_compute_config() hunk due to killing of the
    INTEL_FDI_FREQ check
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.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

@@ -4809,7 +4809,7 @@ static void i9xx_set_pipeconf(struct intel_crtc *intel_crtc)
 		 * XXX: No double-wide on 915GM pipe B. Is that the only reason for the
 		 * pipe == 0 check?
 		 */
-		if (intel_crtc->config.requested_mode.clock >
+		if (intel_crtc->config.adjusted_mode.clock >
 		    dev_priv->display.get_display_clock_speed(dev) * 9 / 10)
 			pipeconf |= PIPECONF_DOUBLE_WIDE;
 	}