SeaBIOS: Fix a bug in PCI ID mapping

This apparently did not hit us before because the option rom
was packed into CBFS with the correct file name but with the
wrong ID.

BUG=chrome-os-partner:3947
TEST=boot coreboot/seabios on alex (needs another change in coreboot)

Change-Id: Ic6573fa07d13c617990e4a2a64bb28e6b45b01db
1 file changed