[Bluetooth] Fix double frees on error paths of btusb and bpa10x drivers

The transfer buffer of an URB will be automatically freed when using
the URB_FREE_BUFFER transfer_flag. So the extra calls to kfree() will
cause a double free.
Reported-by: NJustin Mattock <justinmattock@gmail.com>
Signed-off-by: NRabin Vincent <rabin@rab.in>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/bpa10x.c

@@ -256,7 +256,6 @@ static inline int bpa10x_submit_intr_urb(struct hci_dev *hdev)
 		BT_ERR("%s urb %p submission failed (%d)",
 						hdev->name, urb, -err);
 		usb_unanchor_urb(urb);
-		kfree(buf);
 	}
 
 	usb_free_urb(urb);
@@ -298,7 +297,6 @@ static inline int bpa10x_submit_bulk_urb(struct hci_dev *hdev)
 		BT_ERR("%s urb %p submission failed (%d)",
 						hdev->name, urb, -err);
 		usb_unanchor_urb(urb);
-		kfree(buf);
 	}
 
 	usb_free_urb(urb);

drivers/bluetooth/btusb.c

@@ -271,7 +271,6 @@ static int btusb_submit_intr_urb(struct hci_dev *hdev)
 		BT_ERR("%s urb %p submission failed (%d)",
 						hdev->name, urb, -err);
 		usb_unanchor_urb(urb);
-		kfree(buf);
 	}
 
 	usb_free_urb(urb);
@@ -354,7 +353,6 @@ static int btusb_submit_bulk_urb(struct hci_dev *hdev)
 		BT_ERR("%s urb %p submission failed (%d)",
 						hdev->name, urb, -err);
 		usb_unanchor_urb(urb);
-		kfree(buf);
 	}
 
 	usb_free_urb(urb);
@@ -475,7 +473,6 @@ static int btusb_submit_isoc_urb(struct hci_dev *hdev)
 		BT_ERR("%s urb %p submission failed (%d)",
 						hdev->name, urb, -err);
 		usb_unanchor_urb(urb);
-		kfree(buf);
 	}
 
 	usb_free_urb(urb);