be2net: Fix TX rate limiting on Lancer/Skyhawk-R VFs

When max_tx_rate is set via bw_max in the NIC resource desc, bw_min must be
set to 0.
Signed-off-by: Kalesh AP <kalesh.purayil@emulex.com>

Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>