nm-initrd-generator scans the command line for options relevant to network
configuration and creates configuration files for an early instance of
NetworkManager run from the initial ramdisk during early boot.
This is loosely based on nms-ibft-reader, but with some significant
changes. Notably, it parses /sys/firmware/ibft directly instead of
iscsiadm output.
iscsiadm is not available on early boot (perhaps it's too large) and
turns out that parsing sysfs directly is easier and more
straightforwared anyways. A win-win situation.
It is not useful alone, it's in a separate commit just for the sake of
easier review.
