[SeaBIOS] [PATCH v3] config: allow DEBUG_IO for !QEMU

[Kevin O'Connor]

On Wed, May 29, 2013 at 04:25:59PM +0200, Gerd Hoffmann wrote:
> Allow selecting DEBUG_IO for non-qemu configurations,
> which is useful when running coreboot+seabios on qemu.

Unfortunately, if one does run seabios on real hardware and has
DEBUG_IO enabled, it will write to IO port 0x402 before confirming
that it is actually running on QEMU.  This could cause mysterious
failures on real hardware if something is listening to that port.
It's why I left the option dependent on QEMU instead of QEMU_HARDWARE.
Ideally the code would verify it is on QEMU before using the IO port,
while still providing the very early debugging when it is known to be
safe.

-Kevin