PCI: acpiphp: Remove unused acpiphp_callback typedef

Remove the 'acpiphp_callback' typedef as it is not used.

Link: https://lore.kernel.org/r/1613443120-4279-1-git-send-email-chen45464546@163.comSigned-off-by: Chen Lin <chen.lin5@zte.com.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/pci/hotplug/acpiphp.h

@@ -176,9 +176,6 @@ int acpiphp_unregister_attention(struct acpiphp_attention_info *info);
 int acpiphp_register_hotplug_slot(struct acpiphp_slot *slot, unsigned int sun);
 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *slot);
 
-/* acpiphp_glue.c */
-typedef int (*acpiphp_callback)(struct acpiphp_slot *slot, void *data);
-
 int acpiphp_enable_slot(struct acpiphp_slot *slot);
 int acpiphp_disable_slot(struct acpiphp_slot *slot);
 u8 acpiphp_get_power_status(struct acpiphp_slot *slot);