hw/isa/vt82c686: Route PIRQ inputs using via_isa_set_irq()

hw/isa/vt82c686: Route PIRQ inputs using via_isa_set_irq()

The chip has 4 pins (called PIRQA-D in VT82C686B and PINTA-D in
VT8231) that are meant to be connected to PCI IRQ lines and allow
routing PCI interrupts to the ISA PIC. Route these in
via_isa_set_irq() to make it possible to share them with internal
functions that can also be routed to the same ISA IRQs.

Fixes: 2fdadd02e675caca4aba4ae26317701fe2c4c901
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-ID: <8c4513d8b78fac40e6d4e65a0a4b3a7f2f278a4b.1701035944.git.balaton@eik.bme.hu>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>