of in_port_t and in_addr_t to top of file and use throughout. Use
sa_family_t type where appropriate.
(struct in6_addr): Change `unsigned char' to `uint8_t'.
(struct sockaddr_in6): Add sin6_scope_id member. Add comments.
* include/cygwin/socket.h: Include stdint.h. Move definition of
socklen_t to top of file. Define sa_family_t. Define struct
sockaddr_storage as per SUSv3.
* include/sys/un.h: Include cygwin/socket.h. Use sa_family_t type.