doc: fix PCI whitelist typo in prog guide
doc: fix PCI whitelist typo in prog guide

The placeholder for PCI address should be named DBDF
which stands for Domain/Bus/Device/Function.

Fixes: 33af337773ac ("ethdev: add common devargs parser")
Cc: stable@dpdk.org

Signed-off-by: Thomas Monjalon <5f50a84c1fa3bcff146405017f36aec1a10a9e38@monjalon.net>
Reviewed-by: Rami Rosen <d906574dd7f018d5d95e7b7a8107cdf708745f05@gmail.com>

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