patch 8.2.3912: the ins_complete() function is much too long

Problem:    The ins_complete() function is much too long.
Solution:   Split it up into multiple functions. (Yegappan Lakshmanan,
            closes #9414)
diff --git a/src/version.c b/src/version.c
index 0d99bb8..06a0a33 100644
--- a/src/version.c
+++ b/src/version.c
@@ -750,6 +750,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3912,
+/**/
     3911,
 /**/
     3910,