Update comment in posixmodule.c (GH-5681)

A closing parentheses was missing.

Signed-off-by: Ngie Cooper <yaneurabeya@gmail.com>
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 72fda6a..d242df0 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -6102,7 +6102,7 @@
 #ifdef HAVE_STROPTS_H
 #include <stropts.h>
 #endif
-#endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) || defined(HAVE_DEV_PTMX */
+#endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) || defined(HAVE_DEV_PTMX) */
 
 
 #if defined(HAVE_OPENPTY) || defined(HAVE__GETPTY) || defined(HAVE_DEV_PTMX)