Bluetooth: btusb: Reclassify Qualcomm WCN6855 debug packets

Bluetooth: btusb: Reclassify Qualcomm WCN6855 debug packets

Some Qualcomm Bluetooth controllers, e.g., QCNFA765 with WCN6855
chip, send debug packets as ACL frames with header 0x2EDC.
The kernel misinterprets these as malformed ACL packets, causing
repeated errors:

  Bluetooth: hci0: ACL packet for unknown connection handle 3804

This can occur hundreds of times per minute, greatly cluttering logs.
On my computer, I am observing approximately 7 messages per second
when streaming audio to a speaker.

For Qualcomm controllers exchanging over UART, hci_qca.c already
filters out these debug packets. This patch is for controllers
not going through UART, but USB.

This patch uses the classify_pkt_type callback to reclassify the
packets with handle 0x2EDC as HCI_DIAG_PKT before they reach the
HCI layer. This change is only applied to Qualcomm devices marked
as BTUSB_QCA_WCN6855.

Tested on: Thinkpad T14 gen2 (AMD) with QCNFA765 (0489:E0D0)
Signed-off-by: Pascal Giard <pascal.giard@etsmtl.ca>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>