patch 8.2.5115: search timeout is overrun with some patterns

Problem:    Search timeout is overrun with some patterns.
Solution:   Check for timeout in more places.  Make the flag volatile and
            atomic.  Use assert_inrange() to see what happened.
diff --git a/src/version.c b/src/version.c
index 3edd318..a7e622e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -735,6 +735,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    5115,
+/**/
     5114,
 /**/
     5113,