They are defined by XSI or newer SUS.
This is a follow-up to r318780.
Reported by: jbeich
Obtained from: DragonflyBSD commit e08b3836c962
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Add the POSIX header files
* arpa/inet.h
* net/if.h
* netdb.h
* netinet/in.h
* netinet/tcp.h
* sys/socket.h
* sys/syslog.h
* sys/uio.h
* sys/un.h
* syslog.h
* termios.h
and their dependencies for RTEMS. The origin of these files is the
latest FreeBSD.
Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>