q800: route SONIC on-board Ethernet IRQ via nubus IRQ 9 in classic mode

q800: route SONIC on-board Ethernet IRQ via nubus IRQ 9 in classic mode

When the hardware is operating in classic mode the SONIC on-board Ethernet IRQ is
routed to nubus IRQ 9 instead of directly to the CPU at level 3. This does not
affect the framebuffer which although it exists in slot 9, has its own
dedicated IRQ on the Quadra 800 hardware.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20211020134131.4392-7-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>