patch 8.2.0879: compiler warning for unused function argument

Problem:    Compiler warning for unused function argument.
Solution:   Add UNUSED.
diff --git a/src/version.c b/src/version.c
index 4a27140..80be6d0 100644
--- a/src/version.c
+++ b/src/version.c
@@ -747,6 +747,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    879,
+/**/
     878,
 /**/
     877,