isa: give ISABus/ISADevice to isa_create(), isa_bus_irqs() and isa_get_irq() functions

NULL is a valid bus/device, so there is no change in behaviour.

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/qemu-common.h b/qemu-common.h
index 44870fe52..b2de015 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -217,6 +217,7 @@
 typedef struct VLANClientState VLANClientState;
 typedef struct i2c_bus i2c_bus;
 typedef struct i2c_slave i2c_slave;
+typedef struct ISABus ISABus;
 typedef struct SMBusDevice SMBusDevice;
 typedef struct PCIHostState PCIHostState;
 typedef struct PCIExpressHost PCIExpressHost;