struct pci_ecam_ops embeds a struct pci_ops.  Explicitly request the
definition for struct pci_ops, otherwise gcc might complain:

  include/linux/pci-ecam.h:29:19: error: field 'pci_ops' has incomplete type
Signed-off-by: NMarc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>