doc: announce ABI change for PCI class
doc: announce ABI change for PCI class

The purpose of this patch is used to add a new field
"class" in rte_pci_id structure. The new class field includes
class_id, subcalss_id, programming interface of a pci device.
With this field, we can identify pci device by its class info,
which can be more flexible instead of probing the device by
vendor_id OR device_id OR subvendor_id OR subdevice_id.
For example, we can probe all nvme devices by class field, which
can be quite convenient.

Signed-off-by: Ziye Yang <98fabcbdd507032310947ff9cd228bfb9c69a89b@intel.com>
Acked-by: Bruce Richardson <66b9e8e8fbd5e9f41f91b0af050876182ce9d0e4@intel.com>
Acked-by: Helin Zhang <aba9dfdb1a6ec8bf1ff66b95272c029f8dfde1b1@intel.com>
Acked-by: Cunming Liang <7edc6dd0948177c688da9b288939d80da3db4303@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk