This adds two new buildset configurations: One that leaves out as much
features as possible and one that enables all features. For the default
configuration WiFi support is now disabled.
To disable IPv6 for the minimal configuration, all -DINET6 are
eliminated in libbsd.py. They are now replaced by a #ifdef that checks
for RTEMS_BSD_MODULE_NETINET6 instead.
Close#3351.
The following files are now provided by Newlib:
* arpa/inet.h
* net/if.h
* netinet/in.h
* netinet/tcp.h
* sys/socket.h
* sys/uio.h
* sys/un.h
The <sys/param.h> and <sys/cpuset.h> are now compatible enough to be
used directly.
Update #2833.
