drivers/net: use device name from device structure

drivers/net: use device name from device structure

Device name resides in two different locations, in rte_device->name and
in ethernet device private data.

For now, the copy in the ethernet device private data is required for
multi process support, the name is the how secondary process finds about
primary process device.

But for drivers there is no reason to use the copy in the ethernet
device private data.

This patch updates PMDs to use only rte_device->name.

Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>