ioat: remove unused #defines

IOAT has a redefine of PCI Vendor, PCI Subvendor, etc for
PCI_VENDOR_ID_INTEL but they are never used.  Remove them.

Signed-off-by: Jon Mason <jdmason@kudzu.us>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>