patch 8.0.1439: if cscope fails a search Vim may hang

Problem:    If cscope fails a search Vim may hang.
Solution:   Bail out when a search error is encountered. (Safouane Baroudi,
            closes #2598)
diff --git a/src/version.c b/src/version.c
index f66cf45..09fb300 100644
--- a/src/version.c
+++ b/src/version.c
@@ -772,6 +772,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1439,
+/**/
     1438,
 /**/
     1437,