patch 9.1.0640: Mingw: Makefile can be improved

Problem:  Mingw: Makefile can be improved
Solution: Reduce nesting level, directly check if the '-Wl,--entry'
          option is required (Ken Takata)

closes: #15386

Signed-off-by: Ken Takata <kentkt@csc.jp>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index 97414a0..53c1118 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    640,
+/**/
     639,
 /**/
     638,