Code cleanup: no functional changes
Represent DHCP "origin" as an enum, not a string.

See IBFT standard for location of "origin" field in iBFT table,
and see MS document: http://msdn.microsoft.com/en-us/library/aa366281.aspx
for description of enums, duplicated here in part:

	typedef enum  {
	  IpPrefixOriginOther                = 0,
	  IpPrefixOriginManual,
	  IpPrefixOriginWellKnown,
	  IpPrefixOriginDhcp,
	  IpPrefixOriginRouterAdvertisement,
	  IpPrefixOriginUnchanged            = 16
	} IP_PREFIX_ORIGIN;
fwparam_ibft: Check iBFT target and NIC flags

Check the iBFT NIC and Target flags for valid boot.
Since some adapters correctly set Bit 0 and others
set Bit 1 for NICs, allow either value there.

Signed-off-by: Lee Duncan <lduncan@suse.com>
Allow modifications for iface.gateway and iface.subnet_mask

For proper operations we need to set gateway and subnet_mask
of the individual interfaces. Not every target is connected
to the local network.