[dpdk-dev] Misuses of dev_info->if_index in embedded drivers.

[Stephen Hemminger <stephen@networkplumber.org>]

The use of if_index in some drivers is wrong.
It does not match the user expectation in the documentation.

This code:
dpaa2/dpaa2_ethdev.c:   dev_info->if_index = priv->hw_id;
pfe/pfe_ethdev.c:       dev_info->if_index = internals->id;

Does match:
struct rte_eth_dev_info {
	struct rte_device *device; /** Generic device information */
	const char *driver_name; /**< Device Driver name. */
	unsigned int if_index; /**< Index to bound host interface, or 0 if none.
		Use if_indextoname() to translate into an interface name. */

Also, this code is unnecessary.