net/bonding: inherit maximum Rx packet length

net/bonding: inherit maximum Rx packet length

Instead of a hard-coded maximum receive length, allow the bonded interface
to inherit this limit from the slave interfaces.  This allows
an application that uses jumbo frames to pass realistic values to
rte_eth_dev_configure without causing an error.

Before the bonding interface is configured, allow slaves with any
max_rx_pktlen to be added and remember the lowest of these values as
a candidate value.  During dev_configure, set the bond device's
max_rx_pktlen to the candidate value.  After this point only slaves
with a max_rx_pktlen greater or equal to that of the bonding device
can be added.

If all slaves are removed, the bond device's pktlen is cleared.

Signed-off-by: Eric Kinzie <ehkinzie@gmail.com>
Acked-by: Declan Doherty <declan.doherty@intel.com>