hppa: Fix serial port assignments and pass-through

hppa: Fix serial port assignments and pass-through

This fixes the serial ports in the emulation to behave as on original
hardware.

On the real hardware, the LASI UART is serial port #0 and the DINO UART
is serial port #1. This is fixed in SeaBIOS-hppa firmware v6, which is
why at least this firmware version is required.

The serial port addresses in hppa/hppa_hardware.h have to be swapped,
and when creating the virtual serial ports the correct port addresses
are used.

This patch now for example allows to specify on the qemu command line:
     -serial mon:stdio -serial /dev/ttyS4
to use the emulated ttyS0 in the guest for console output, and pass
ttyS4 from the host to ttyS1 in the guest.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>