PCI: Use bitfield instead of bool for struct pci_vpd_pci22.busy

Make struct pci_vpd_pci22.busy a 1-bit field instead of a bool.  We intend
to add another flag, and two bitfields are cheaper than two bools.

Tested-by: Shane Seymour <shane.seymour@hpe.com>
Tested-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>