PCI/sysfs: Constify struct kobj_type pci_slot_ktype

Since commit ee6d3dd ("driver core: make kobj_type constant.") the
driver core allows the usage of const struct kobj_type.

Take advantage of this to constify the structure definition to prevent
modification at runtime.

Link: https://lore.kernel.org/r/20230216-kobj_type-pci-v1-1-46a63c8612b5@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Author: t-8ch

drivers/pci/slot.c

@@ -98,7 +98,7 @@ static struct attribute *pci_slot_default_attrs[] = {
 };
 ATTRIBUTE_GROUPS(pci_slot_default);
 
-static struct kobj_type pci_slot_ktype = {
+static const struct kobj_type pci_slot_ktype = {
 	.sysfs_ops = &pci_slot_sysfs_ops,
 	.release = &pci_slot_release,
 	.default_groups = pci_slot_default_groups,