patch 8.0.0494: build failure with older compiler on MS-Windows

Problem:    Build failure with older compiler on MS-Windows.
Solution:   Move declaration to start of block.
diff --git a/src/version.c b/src/version.c
index 72516f0..343b856 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    494,
+/**/
     493,
 /**/
     492,