Enable console POST codes by default

This maintains repsonsiveness of console / IPMI
during the IPL process.

With previous changes in the Zephyr configuration
and Web services controllers, this allows file uploads
and downloads to function while fixing the simultaneous
connection stall problem seen previously.

This is in preparation for adding a Redfish protocol
server.

Fast read and quad SPI are not supported by all Flash
devices / board wiring schemes.  Only enable them if
the detected and configured device supports them.

Framework now in place for further expansion

This avoids having to cache the PNOR at BMC startup, at
a small IPL speed cost.

This avoids lockups seen on detach / reattach
when the host IPL is in process.

This avoids LPC bus stalls and timeouts on host I/O
accesses when the BMC is under heavy CPU load.

Add missing files to repository
Update README with current build instructions

Tested to properly IPL and allow console interaction
with the host over the Zephyr UART shell.

FSI interface seems stable at this point, and the debug spew to
console is not particularly useful for future development of the
BMC firmware.

Note that this embeds a power limit, which may be board/system specific.

This resolves IPL failures with the current FPGA images