netdev-dpdk: Retry tx/rx queue setup until we don't get any failure.

netdev-dpdk: Retry tx/rx queue setup until we don't get any failure.

It has been observed that some DPDK device (e.g intel xl710) report an
high number of queues but make some of them available only for special
functions (SRIOV).  Therefore the queues will be counted in
rte_eth_dev_info_get(), but rte_eth_tx_queue_setup() will fail.

This commit works around the issue by retrying the device initialization
with a smaller number of queues, if a queue fails to setup.

Reported-by: Ian Stokes <ian.stokes@intel.com>
Tested-by: Ian Stokes <ian.stokes@intel.com>
Acked-by: Kevin Traynor <kevin.traynor@intel.com>
Signed-off-by: Daniele Di Proietto <diproiettod@vmware.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>