* environ.cc (struct parse_thing): Add entry for new CYGWIN option

    * environ.cc (struct parse_thing): Add entry for new CYGWIN option
        `smbntsec'.
        * path.cc (path_conv::check): Check path for being a remote path.
        If so and `allow_smbntsec' is set to FALSE, set has_acls to FALSE.
        * security.cc: Add global definition for `allow_smbntsec'.
        * security.h: Add extern declaration for `allow_smbntsec'.
        * fhandler.cc (fhandler_disk_file::open): Eliminate extern declaration
        of `allow_ntsec'.
        * syscalls.cc: Ditto.