Bluetooth: btqca: Use correct byte format for opcode of injected command

The opcode of the command injected by commit 32646db8 ("Bluetooth:
btqca: inject command complete event during fw download") uses the CPU
byte format, however it should always be little endian. In practice it
shouldn't really matter, since all we need is an opcode != 0, but still
let's do things correctly and keep sparse happy.

Fixes: 32646db8 ("Bluetooth: btqca: inject command complete event during fw download")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>