Test case has been updated to verify that `pc_reported_len == offsetof(struct pci_conf, pc_spare)`.
This works on both 32 and 64 bit binaries:
```
[root@freebsd ~/tests/pci]$ ./pci15 | tail
vendor: 32902
device: 4110
class: 2
subclass: 0
progif: 0
revid: 3
driver: em
unit: 0
NUMA node: 0
Reported length: 64
[root@freebsd ~/tests/pci]$ ./pci15_32 | tail
vendor: 32902
device: 4110
class: 2
subclass: 0
progif: 0
revid: 3
driver: em
unit: 0
NUMA node: 0
Reported length: 52
```