drm/i915: Update DRIVER_DATE to 20180906

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drivers/gpu/drm/i915/i915_drv.h

@@ -87,7 +87,7 @@
 #define DRIVER_NAME		"i915"
 #define DRIVER_DESC		"Intel Graphics"
 #define DRIVER_DATE		"20180906"
-#define DRIVER_TIMESTAMP	1536236058
+#define DRIVER_TIMESTAMP	1536241554
 
 /* Use I915_STATE_WARN(x) and I915_STATE_WARN_ON() (rather than WARN() and
  * WARN_ON()) for hw state sanity checks to check for unexpected conditions