hw/isa/piix3: Modernize reset handling

Rather than registering the reset handler via a function which
appends the handler to a global list, prefer to implement it as
a virtual method - PIIX4 does the same already.

Note that this means that piix3_reset can now also be called writing to
the relevant configuration space register on a PCI bridge.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20221022150508.26830-6-shentey@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

hw/isa/piix3.c

@@ -31,7 +31,6 @@
 #include "hw/isa/isa.h"
 #include "hw/xen/xen.h"
 #include "sysemu/xen.h"
-#include "sysemu/reset.h"
 #include "sysemu/runstate.h"
 #include "migration/vmstate.h"
 #include "hw/acpi/acpi_aml_interface.h"
@@ -156,9 +155,9 @@ static void piix3_write_config_xen(PCIDevice *dev,
     piix3_write_config(dev, address, val, len);
 }
 
-static void piix3_reset(void *opaque)
+static void piix3_reset(DeviceState *dev)
 {
-    PIIX3State *d = opaque;
+    PIIX3State *d = PIIX3_PCI_DEVICE(dev);
     uint8_t *pci_conf = d->dev.config;
 
     pci_conf[0x04] = 0x07; /* master, memory and I/O */
@@ -313,8 +312,6 @@ static void pci_piix3_realize(PCIDevice *dev, Error **errp)
     memory_region_add_subregion_overlap(pci_address_space_io(dev),
                                         PIIX_RCR_IOPORT, &d->rcr_mem, 1);
 
-    qemu_register_reset(piix3_reset, d);
-
     i8257_dma_init(isa_bus, 0);
 }
 
@@ -337,6 +334,7 @@ static void pci_piix3_class_init(ObjectClass *klass, void *data)
     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
     AcpiDevAmlIfClass *adevc = ACPI_DEV_AML_IF_CLASS(klass);
 
+    dc->reset       = piix3_reset;
     dc->desc        = "ISA bridge";
     dc->vmsd        = &vmstate_piix3;
     dc->hotpluggable   = false;