hci_coredump_qca() uses __hci_cmd_sync() to send a vendor-specific command
to trigger firmware coredump, but the command does not have any event as
its sync response, so it is not suitable to use __hci_cmd_sync(), fixed by
using __hci_cmd_send().

Fixes: 06d3fdfc ("Bluetooth: hci_qca: Add qcom devcoredump support")
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>