USB: option: reduce interrupt-urb logging verbosity

Do not log normal interrupt-urb shutdowns as errors.

The option driver has always been logging any nonzero interrupt-urb
status as an error, including when the urb is killed during normal
operation.

Commit 9096f1fbba91 ("USB: usb_wwan: fix potential NULL-deref at
resume") moved the interrupt urb submission from port probe and release
to open and close, thus potentially increasing the number of these
false-positive error messages dramatically.

Reported-by: Ed Butler <ressy66@ausics.net>
Tested-by: Ed Butler <ressy66@ausics.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index a968894..34f142b 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -1916,6 +1916,8 @@
 			dev_dbg(dev, "%s: type %x req %x\n", __func__,
 				req_pkt->bRequestType, req_pkt->bRequest);
 		}
+	} else if (status == -ENOENT || status == -ESHUTDOWN) {
+		dev_dbg(dev, "%s: urb stopped: %d\n", __func__, status);
 	} else
 		dev_err(dev, "%s: error %d\n", __func__, status);