accept iodevices as NACs as well

accept iodevices as NACs as well

Assignable PCIe devices have a root complex path and a more descriptive
I/O slot path;  example output from a T4-2:

	# ldomctl list-io | head -n2
	PATH             NAME
	/@400/@2/@0/@8   /SYS/MB/PCIE0

ldom.conf(5) `iodevice' currently accepts PATH values, which are cryptic and
completely hardware specific, whereas NAME values are obvious (partially
same across machines) and match physical slot labels ("0 PCIe2 x8") besides
information from ILOM:
    /System/PCI_Devices/Add-on/Device_0 location = PCIE0 (PCIe Slot 0).

Make ldom.conf `iodevice' accept either value;  internally nothing changes.

Rename struct iodev's path member to dev to clarify this further.

OK kettenis