When KNI is being used at runtime, output a warning message about its
deprecated status. This is part of the deprecation process for KNI
agreed by the DPDK technical board.[1]
[1] https://mails.dpdk.org/archives/dev/2022-June/243596.html
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>