patch 8.2.0689: when using getaddrinfo() the error message is unclear

Problem:    When using getaddrinfo() the error message is unclear.
Solution:   Use gai_strerror() to get the message. (Ozaki Kiichi,
            closes #6034)

src/version.c

@@ -746,6 +746,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    689,
 /**/
     688,
 /**/