patch 9.0.0740: prop_add_list() gives multiple errors for invalid argument

Problem:    prop_add_list() gives multiple errors for invalid argument.
Solution:   Only give one error message.

src/version.c

@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    740,
 /**/
     739,
 /**/