Bluetooth: L2CAP: Fix printing wrong information if SDU length exceeds MTU

Bluetooth: L2CAP: Fix printing wrong information if SDU length exceeds MTU

The code was printing skb->len and sdu_len in the places where it should
be sdu_len and chan->imtu respectively to match the if conditions.

Link: https://lore.kernel.org/linux-bluetooth/20260315132013.75ab40c5@kernel.org/T/#m1418f9c82eeff8510c1beaa21cf53af20db96c06
Fixes: e1d9a6688986 ("Bluetooth: LE L2CAP: Disconnect if received packet's SDU exceeds IMTU")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>