patch 8.2.2978: warning for uninitialized variable

Problem:    Warning for uninitialized variable.
Solution:   Set return value to FAIL.
diff --git a/src/version.c b/src/version.c
index 19a159d..6ae66ae 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2978,
+/**/
     2977,
 /**/
     2976,