[hci] Expose ifcommon_exec() in a local header so wireless commands can use it
This keeps code size down, since the wireless interface management
commands have the same command-line interface and overall structure as
the wired commands.
Signed-off-by: Michael Brown <mcb30@etherboot.org>
Strip down i386 PCI configuration space I/O to the bare minimum. A
typical build will now include 880 bytes of PCI support code, compared to
2327 bytes in Etherboot 5.4.
(There is a slight cost of around 5 extra bytes per access to a
non-constant config space address; this should be an overall win.
Driver-specific accesses will usually be to constant addresses, for
which there is no additional cost.)