patch 8.0.0884: can't specify the wait time for term_wait()

Problem:    Can't specify the wait time for term_wait().
Solution:   Add an otional second argument.
diff --git a/src/version.c b/src/version.c
index e6bcfb5..e318114 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    884,
+/**/
     883,
 /**/
     882,