LinuxKPI: pci.h / linux_pci.c rename pci_driver field

Rename the struct pci_driver {} field to the list_head from links
to node as a driver is actually initialsing this to {} which seems
questionable but it will at least make us match the Linux structure
field name.

Reviewed by: manu, hselasky

(cherry picked from commit cf899348420ce8839e32ddc30247b5d1c2b384f4)