patch 7.4.812

Problem:    Gcc sanitizer complains about using a NULL pointer to memmove().
Solution:   Only call memmove when there is something to move. (Vittorio
            Zecca)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    812,
 /**/
     811,
 /**/