patch 9.0.1513: text scrolls unnecessarily when splitting

Problem:    Text scrolls unnecessarily when splitting and 'splitkeep' is not
            "cursor".
Solution:   Avoid resetting w_skipcol. (Luuk van Baal, closes #12334)

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1513,
 /**/
     1512,
 /**/