CVE-2026-11894 Double-free / use-after-free in Realtek BEE Bluetooth HCI driver `send()` error paths

The Realtek BEE Bluetooth HCI driver's send callback, bthcibeesend in drivers/bluetooth/hci/hcibee.c, violated the bthcidriverapi buffer-ownership contract. That contract requires the driver to consume unref the transmit netbuf only on success; on an error return the host caller retains ownership...