Fix some bugs in the FreeBSD 4/5/6 pci(4) IOCTLs compatibility code:

• Use the correct offsets when copying out the results of PCIOCGETCONF_OLD. This happened to not affect the 64-bit architectures because there the addition of pc_domain to struct pcisel didn't change the overall size of struct pci_conf. [1]
• Always copy the name and unit information to conf_old so it's also part of the output once this information is cached in dinfo.
• Use the correct type for flags in struct pci_match_conf_old. This change is more or less cosmetic though.

Reported and tested by: bde [1]
Reviewed by: imp
MFC after: 3 days
Committed from: 24C3