bridge: make buffer larger in br_setlink()

We pass IFLA_BRPORT_MAX to nla_parse_nested() so we need
IFLA_BRPORT_MAX + 1 elements.  Also Smatch complains that we read past
the end of the array when in br_set_port_flag() when it's called with
IFLA_BRPORT_FAST_LEAVE.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>