patch 9.1.1373: 'completeopt' checking logic can be simplified

Problem:  Flag checking logic uses a temporary variable and multiple
          bitwise operations in insexpand.c
Solution: Consolidate into a single equality check using bitwise OR and
          comparison (glepnir)

closes: #17276

Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1373,
 /**/
     1372,
 /**/