ChangeLog.txt:  Update anticapted release year for nuttx-8.3
* netutils/netlib/netlib_getdevs.c: Add comments and a placeholder for the
RTM_NEWROUTE response. From Gregory Nutt (2019-11-12).
-8.3 2019-xx-xx Gregory Nutt <gnutt@nuttx.org>
+8.3 2020-xx-xx Gregory Nutt <gnutt@nuttx.org>
