hw/isa/vt82c686: Implement relocation and toggling of SuperI/O functions

hw/isa/vt82c686: Implement relocation and toggling of SuperI/O functions

The VIA south bridges are able to relocate and toggle (enable or disable) their
SuperI/O functions. So far this is hardcoded such that all functions are always
enabled and are located at fixed addresses.

Some PC BIOSes seem to probe for I/O occupancy before activating such a function
and issue an error in case of a conflict. Since the functions are currently
enabled on reset, conflicts are always detected. Prevent that by implementing
relocation and toggling of the SuperI/O functions.

Note that all SuperI/O functions are now deactivated upon reset (except for
VT82C686B's serial ports where Fuloong 2e's rescue-yl seems to expect them to be
enabled by default). Rely on firmware to configure the functions accordingly.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-Id: <20240114123911.4877-12-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>