drm/i915: Update DRIVER_DATE to 20151218

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.h

@@ -58,7 +58,7 @@
 
 #define DRIVER_NAME		"i915"
 #define DRIVER_DESC		"Intel Graphics"
-#define DRIVER_DATE		"20151204"
+#define DRIVER_DATE		"20151218"
 
 #undef WARN_ON
 /* Many gcc seem to no see through this and fall over :( */