We thought it was a good idea to terminate channel subds, but we included onchaind as well!
```
2025-01-29T21:31:46.053Z UNUSUAL 03…00-channeld-chan#255683: Adding HTLC 1737 too slow: killing connection
2025-01-29T21:31:46.053Z INFO 03…00-chan#255683: Peer transient failure in CHANNELD_NORMAL: Adding HTLC timed out: killed connection
2025-01-29T21:31:46.053Z DEBUG 03…00-channeld-chan#255683: Status closed, but not exited. Killing
2025-01-29T21:31:46.054Z DEBUG 03…00-chan#255683: Failing HTLC 1738 due to peer death
2025-01-29T21:31:46.058Z DEBUG 03…00-chan#255683: Failing HTLC 1737 due to peer death
2025-01-29T21:31:46.058Z DEBUG 03…00-chan#255673: Forcing disconnect due to One channel had an error
2025-01-29T21:31:46.059Z DEBUG 03…00-onchaind-chan#255673: Status closed, but not exited. Killing
2025-01-29T21:31:46.093Z DEBUG 03…00-connectd: disconnect_peer
2025-01-29T21:31:46.093Z DEBUG 03…00-lightningd: peer_disconnect_done
```
Reported-by: @whitslack
Fixes: https://github.com/ElementsProject/lightning/issues/8055
Changelog-Fixed: onchaind: don't die if we fail an unrelated channel with the same peer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>