patch 8.0.1664: test failure because of not allocating enough space

Problem:    Test failure because of not allocating enough space.
Solution:   Allocate more bytes.

src/version.c

@@ -762,6 +762,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1664,
 /**/
     1663,
 /**/