Bluetooth: btmtk: Fix wait_on_bit_timeout interruption during shutdown

During the shutdown process, an interrupt occurs that
prematurely terminates the wait for the expected event.
This change replaces TASK_INTERRUPTIBLE with
TASK_UNINTERRUPTIBLE in the wait_on_bit_timeout call to ensure
the shutdown process completes as intended without being
interrupted by signals.

Fixes: d019930b0049 ("Bluetooth: btmtk: move btusb_mtk_hci_wmt_sync to btmtk.c")
Signed-off-by: Jiande Lu <[e-mail]>
Signed-off-by: Luiz Augusto von Dentz <[e-mail]>

drivers/bluetooth/btmtk.c

···
 	 * WMT command.
 	 */
 	err = wait_on_bit_timeout(&data->flags, BTMTK_TX_WAIT_VND_EVT,
-				  TASK_INTERRUPTIBLE, HCI_INIT_TIMEOUT);
-	if (err == -EINTR) {
-		bt_dev_err(hdev, "Execution of wmt command interrupted");
-		clear_bit(BTMTK_TX_WAIT_VND_EVT, &data->flags);
-		goto err_free_wc;
-	}
+				  TASK_UNINTERRUPTIBLE, HCI_INIT_TIMEOUT);
 
 	if (err) {
 		bt_dev_err(hdev, "Execution of wmt command timed out");