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.
In case of WPA on a WiFi interface, the interface isn't yet ready when
the dhcpcd starts. Sending a packet during that time returns with a
ENOBUFS. That caused the interface to be ignored.
On the upstream repository of dhcpcd, that transient error (and some
others) are already ignored.
