Fix the <NULL> driver name reported by "ifstat" when using the undipci
driver (due to the unnecessary extra device node inserted as a child
of the PCI device).

Remove the "UNDI-" prefix from device names since the driver name is
also now visible via "ifstat", and tidy up the device name to match
the format used by standard PCI devices.

The output from "ifstat" now resembles:

  iPXE> ifstat
  net0: 52:54:00:12:34:56 using undipci on 0000:00:03.0

  iPXE> ifstat
  net0: 52:54:00:12:34:56 using undionly on 0000:00:03.0

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Move most arch/i386 files to arch/x86, and adjust the contents of the
Makefiles and the include/bits/*.h headers to reflect the new
locations.

This patch makes no substantive code changes, as can be seen using a
rename-aware diff (e.g. "git show -M5").

This patch does not make the pcbios platform functional for x86_64; it
merely allows it to compile without errors.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Relicense files for which I am the sole author (as identified by
util/relicense.pl).

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Add FILE_LICENCE declarations to almost all files that make up the
various standard builds of gPXE.

function prefix "undinet_" and the variable name "undinic" in undinet.c,
so that we can reserve the variable name "undi" for a struct undi_device.

The idea is that we preserve the Etherboot 5.4 convention that the "UNDI"
code refers to our using an underlying UNDI stack, while the "PXE" code
refers to our providing a PXE API.