patch 8.1.1648: MS-Windows: build error with normal feaures

Problem:    MS-Windows: build error with normal feaures.
Solution:   Adjust #ifdef for find_word_under_cursor().
diff --git a/src/version.c b/src/version.c
index 5cf7da3..4952b70 100644
--- a/src/version.c
+++ b/src/version.c
@@ -778,6 +778,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1648,
+/**/
     1647,
 /**/
     1646,