drm/i915: Don't try to initialize sprite planes on pre-ilk

We don't currently implement support for sprite planes on pre-ilk
platforms, so let's leave num_sprites at 0 so that we don't get
spurious errors during driver init.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477411083-19255-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
index d6a8f11..185e3bb 100644
--- a/drivers/gpu/drm/i915/intel_device_info.c
+++ b/drivers/gpu/drm/i915/intel_device_info.c
@@ -282,12 +282,13 @@ void intel_device_info_runtime_init(struct drm_i915_private *dev_priv)
 		info->num_sprites[PIPE_A] = 2;
 		info->num_sprites[PIPE_B] = 2;
 		info->num_sprites[PIPE_C] = 1;
-	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
+	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
 		for_each_pipe(dev_priv, pipe)
 			info->num_sprites[pipe] = 2;
-	else
+	} else if (INTEL_GEN(dev_priv) >= 5) {
 		for_each_pipe(dev_priv, pipe)
 			info->num_sprites[pipe] = 1;
+	}
 
 	if (i915.disable_display) {
 		DRM_INFO("Display disabled (module parameter)\n");