patch 8.0.1614: "make tags" doesn't include libvterm

Problem:    "make tags" doesn't include libvterm.
Solution:   Add the libvterm sources to the tags command.
diff --git a/src/version.c b/src/version.c
index b5c6137..5d52bc9 100644
--- a/src/version.c
+++ b/src/version.c
@@ -767,6 +767,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1614,
+/**/
     1613,
 /**/
     1612,