mac_via: workaround NetBSD ADB bus enumeration issue

mac_via: workaround NetBSD ADB bus enumeration issue

NetBSD assumes it can send its first ADB command after sending the ADB_BUSRESET
command in ADB_STATE_NEW without changing the state back to ADB_STATE_IDLE
first as detailed in the ADB protocol.

Add a workaround to detect this condition at the start of ADB enumeration
and send the next command written to SR after a ADB_BUSRESET onto the bus
regardless, even if we don't detect a state transition to ADB_STATE_NEW.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <20231004083806.757242-16-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>