patch 8.2.0880: leaking memory when using searchcount()

Problem:    Leaking memory when using searchcount().
Solution:   Free the last used search pattern.
diff --git a/src/version.c b/src/version.c
index 80be6d0..3a74509 100644
--- a/src/version.c
+++ b/src/version.c
@@ -747,6 +747,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    880,
+/**/
     879,
 /**/
     878,