net/i40e: set min and max MTU for VF
net/i40e: set min and max MTU for VF

This commit sets the min and max supported MTU values for i40e VF
devices via the i40evf_dev_info_get() function. Min MTU supported
is set to ETHER_MIN_MTU and max MTU is calculated as the max packet
length supported minus the transport overhead.

Signed-off-by: Ian Stokes <d6de0b34eaa7eae4498133a8396f9d6a9816c6b1@intel.com>
Reviewed-by: Ferruh Yigit <ba8734c3c506d2e3557bd4ac8fdaccd25bdb9aa7@intel.com>

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