bump driver version

Author: Nir-Az

kernel/realsense/d4xx.c

@@ -5639,4 +5639,4 @@ MODULE_AUTHOR("Guennadi Liakhovetski <guennadi.liakhovetski@intel.com>,\n\
 				Shikun Ding <shikun.ding@intel.com>");
 MODULE_AUTHOR("Dmitry Perchanov <dmitry.perchanov@intel.com>");
 MODULE_LICENSE("GPL v2");
-MODULE_VERSION("1.0.1.20");
+MODULE_VERSION("1.0.1.21");