PCI: hotplug: Remove "Returns" kerneldoc from void functions

pci_hp_deregister() was converted to void by the commit 51bbf9b ("PCI:
hotplug: Demidlayer registration with the core") but its kerneldoc still
describes the return value. pci_hp_del() and pci_hp_destroy() have been
void since they were introduced in that same commit.

Remove the return value description from the kerneldoc of those functions.

Link: https://lore.kernel.org/r/20240930124436.17908-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/hotplug/pci_hotplug_core.c

@@ -498,8 +498,6 @@ EXPORT_SYMBOL_GPL(pci_hp_add);
  *
  * The @slot must have been registered with the pci hotplug subsystem
  * previously with a call to pci_hp_register().
- *
- * Returns 0 if successful, anything else for an error.
  */
 void pci_hp_deregister(struct hotplug_slot *slot)
 {
@@ -513,8 +511,6 @@ EXPORT_SYMBOL_GPL(pci_hp_deregister);
  * @slot: pointer to the &struct hotplug_slot to unpublish
  *
  * Remove a hotplug slot's sysfs interface.
- *
- * Returns 0 on success or a negative int on error.
  */
 void pci_hp_del(struct hotplug_slot *slot)
 {
@@ -545,8 +541,6 @@ EXPORT_SYMBOL_GPL(pci_hp_del);
  * the driver may no longer invoke hotplug_slot_name() to get the slot's
  * unique name.  The driver no longer needs to handle a ->reset_slot callback
  * from this point on.
- *
- * Returns 0 on success or a negative int on error.
  */
 void pci_hp_destroy(struct hotplug_slot *slot)
 {