doc: add large iavf support to release notes
doc: add large iavf support to release notes

Update release note for large VF, supporting up to 256 queue pairs per
VF.

Fixes: e436cd43835b ("net/iavf: negotiate large VF and request more queues")

Signed-off-by: Ting Xu <a22634c400745d700c462bf72fa5f6133709058f@intel.com>
Acked-by: Qi Zhang <9e9e58ffa71a29bb7b87766b362515be648fcbe0@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk