net/iavf: set min and max MTU for VF
net/iavf: set min and max MTU for VF

This commit sets the min and max supported MTU values for iavf VF
devices via the iavf_dev_info_get() function. Min MTU supported
is set to RTE_ETHER_MIN_MTU and max MTU is calculated as the max
packet length supported minus the transport overhead.

Signed-off-by: Robin Zhang <1d4fcb3703779d01de6e23c55c4a436190c2a25e@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