patch 9.0.0108: configure check for timer_create may give wrong error

Problem:    Configure check for timer_create may give wrong error.
Solution:   Give a warning instead of an error.
diff --git a/src/version.c b/src/version.c
index 79802aa..80bd894 100644
--- a/src/version.c
+++ b/src/version.c
@@ -736,6 +736,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    108,
+/**/
     107,
 /**/
     106,