sysbus: remove unused function sysbus_del_io

Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

hw/core/sysbus.c

@@ -242,11 +242,6 @@ void sysbus_add_io(SysBusDevice *dev, hwaddr addr,
     memory_region_add_subregion(get_system_io(), addr, mem);
 }
 
-void sysbus_del_io(SysBusDevice *dev, MemoryRegion *mem)
-{
-    memory_region_del_subregion(get_system_io(), mem);
-}
-
 MemoryRegion *sysbus_address_space(SysBusDevice *dev)
 {
     return get_system_memory();

include/hw/sysbus.h

@@ -71,7 +71,6 @@ void sysbus_mmio_map_overlap(SysBusDevice *dev, int n, hwaddr addr,
                              int priority);
 void sysbus_add_io(SysBusDevice *dev, hwaddr addr,
                    MemoryRegion *mem);
-void sysbus_del_io(SysBusDevice *dev, MemoryRegion *mem);
 MemoryRegion *sysbus_address_space(SysBusDevice *dev);
 
 /* Legacy helper function for creating devices.  */