hw/acpi/cpu_hotplug: Include "hw/pci/pci.h"

hw/acpi/cpu_hotplug: Include "hw/pci/pci.h"

hw/acpi/cpu_hotplug.c calls pci_address_space_io(). Include
"hw/pci/pci.h" which declares it.

This fixes (when modifying unrelated headers):

  hw/acpi/cpu_hotplug.c:103:28: error: implicit declaration of function 'pci_address_space_io' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
      MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe_cpu->device));
                             ^

Acked-by: John Snow <[email protected]>
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
Reviewed-by: Richard Henderson <[email protected]>
Message-Id: <20200228114649[email protected]>
Signed-off-by: Laurent Vivier <[email protected]>