net/bonding: fix link speed update in broadcast mode

net/bonding: fix link speed update in broadcast mode

Fix the issue that the link speed of the bond device was set to the
link speed of the first active slave in broadcast mode.

Set the link speed of the bond device to the minimum value across
all of the slaves in that case.

Fixes: deba8a2f8b0b ("net/bonding: fix link properties management")
Cc: stable@dpdk.org
Signed-off-by: Igor Romanov <igor.romanov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Chas Williams <chas3@att.com>