patch 9.0.0520: declaring a loop variable at the start of a block is clumsy

Problem:    Declaring a loop variable at the start of a block is clumsy.
Solution:   Declare the variable inside the loop in a few places to see if
            this works.

src/version.c

@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    520,
 /**/
     519,
 /**/