Merge branch 'bond-fix-2-link-state-issues'

Hangbin Liu says:

====================
bond: fix 2 link state issues

This patch set fixes two bonding link state issues:

1. Broadcast mode incorrectly sets usable_slaves, causing updelay to be ignored
2. BOND_LINK_FAIL and BOND_LINK_BACK are treated as invalid states, generating
   confusing error messages

Here is the reproducer:

```
ip netns add ns
ip -n ns link add bond0 type bond mode 3 miimon 100 updelay 200 downdelay 200
ip -n ns link add type veth
ip -n ns link add type veth
ip -n ns link set veth1 up
ip -n ns link set veth3 up
ip -n ns link set veth0 master bond0
ip -n ns link set veth2 master bond0
ip -n ns link set bond0 up
sleep 1
ip -n ns link set veth3 down
sleep 1
ip -n ns link set veth3 up
sleep 1
dmesg | tail
```
====================

Link: https://patch.msgid.link/20260304-b4-bond_updelay-v1-0-f72eb2e454d0@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>