closes bpo-44751: Move crypt.h include from public header to _cryptmodule (GH-27394) (GH-28636)

Automerge-Triggered-By: GH:benjaminp
(cherry picked from commit 196998e220d6ca030e5a1c8ad63fcaed8e049a98)

Co-authored-by: Geoffrey Thomas <geofft@ldpreload.com>
diff --git a/Modules/_cryptmodule.c b/Modules/_cryptmodule.c
index a95f55a..72a4f44 100644
--- a/Modules/_cryptmodule.c
+++ b/Modules/_cryptmodule.c
@@ -4,6 +4,9 @@
 #include "Python.h"
 
 #include <sys/types.h>
+#ifdef HAVE_CRYPT_H
+#include <crypt.h>
+#endif
 
 /* Module crypt */