PCI: Fix kernel-doc issues

Fix kernel-doc issues reported by
"find include -name \*pci\* | xargs scripts/kernel-doc -none":

  include/linux/pci.h:731: warning: Function parameter or member 'pdev' not described in 'pci_is_vga'
  include/linux/pci-epc.h:154: warning: Function parameter or member 'list_lock' not described in 'pci_epc'
  include/linux/pci-epf.h:83: warning: expecting prototype for struct pci_epf_event_ops. Prototype was for struct pci_epc_event_ops instead

Link: https://lore.kernel.org/r/20240111162850.2177655-1-helgaas@kernel.org
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Sui Jingfeng <suijingfeng@loongson.cn>