Have the directory reader use the Unix API on VMS
opendir(), readdir() and closedir() have been available on VMS since
version 7.0.
#include "internal/o_dir.h"
#define LPDIR_H
-#if defined OPENSSL_SYS_UNIX || defined DJGPP
+#if defined OPENSSL_SYS_UNIX || defined DJGPP \
+ (defined __VMS_VER && __VMS_VER >= 70000000)
# include "LPdir_unix.c"
#elif defined OPENSSL_SYS_VMS
# include "LPdir_vms.c"
