When possible, network drivers are now started automatically. That
means that netconf(8)'s network driver selection has become obsolete.
This patch changes netconf(8) to allow the user to specify a network
configuration (currently one of DHCP IPv4+IPv6, DHCP IPv4-only,
manual IPv4-only) for any hardware network interfaces that are
currently present.
Selection of network drivers that require manual configuration first
(mainly old ISA cards) is still supported, but now as a special case.
Change-Id: I6208fc75192eb7f0b061862aaf7507f71a620da4
9a8b4f5601