patch 9.0.0918: MS-Windows: modifier keys do not work with mouse scroll event

Problem:    MS-Windows: modifier keys do not work with mouse scroll events.
Solution:   Use K_SPECIAL instead of CSI for the modifier keys. (Christopher
            Plewright, closes #11587)

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    918,
 /**/
     917,
 /**/