patch 9.1.0066: gcc complains about use of uninitialized var

Problem:  gcc complains about use of uninitialized var
          (Tony Mechelynck, after 9.1.0064)
Solution: initialize button to silence gcc

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index b361a9c..d12d4e1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    66,
+/**/
     65,
 /**/
     64,