patch 8.0.0550: cannot parse some etags format tags file

Problem:    Some etags format tags file use 0x01, breaking the parsing.
Solution:   Use 0x02 for TAG_SEP. (James McCoy, closes #1614)
diff --git a/src/version.c b/src/version.c
index 1ffb655..aba7a80 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    550,
+/**/
     549,
 /**/
     548,