patch 9.0.0172: trying to allocate zero bytes

Problem:    Trying to allocate zero bytes.
Solution:   Do not allocate the proptype array when there are none.
            (closes #10867)

src/version.c

@@ -735,6 +735,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    172,
 /**/
     171,
 /**/