In NETMAP mode not all queues need to be allocated to NETMAP. Some of
them could be left to the kernel. Configuration is managed by the flags
nr_mode and nr_pending_mode provided per each NETMAP kring.
ENA driver checks those flags and perform proper rings initialization.
Submitted by: Rafal Kozik <firstname.lastname@example.org>
Michal Krawczyk <email@example.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.