This avoids registering PMDs that are not used by a given
application. For example, an app may wish to *not* use
ioat - in this case, ioat PMD would not be registered with
DPDK, and we would not waste time probing these devices
when probing other devices like NVMe.
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: If378e40bde9057c7808603aa1918bcfe80fa0e9d