This is used to indicate the network dracut module should fall back to
configure network automatically (as with ip=dhcp was specified) if
there's no other network configuration present on the command line.
The option is documented in dracut.cmdline(7).
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/merge_requests/167
NMIPAddr contains an unnamed union. We have to either explicitly
initialize one field, or omit it.
../shared/nm-utils/nm-shared-utils.c:38:36: error: suggest braces around initialization of subobject [-Werror,-Wmissing-braces]
const NMIPAddr nm_ip_addr_zero = { 0 };
^
{}
