rtnetlink: Do not generate notifications for NETDEV_CHANGE_TX_QUEUE_LEN event

Changing tx queue length generates identical messages:

[LINK]22: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default
    link/ether 02:04:f4:b7:5c:d2 brd ff:ff:ff:ff:ff:ff promiscuity 0
    dummy numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
[LINK]22: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default
    link/ether 02:04:f4:b7:5c:d2 brd ff:ff:ff:ff:ff:ff promiscuity 0
    dummy numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535

Remove NETDEV_CHANGE_TX_QUEUE_LEN from the list of notifiers that generate
notifications.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>