wifi: mt76: mt76u_vendor_request: Do not print error messages when -EPROTO

wifi: mt76: mt76u_vendor_request: Do not print error messages when -EPROTO

When initializing the network card, unplugging the device will
trigger an -EPROTO error, resulting in a flood of error messages
being printed frantically.

The exception is printed as follows：

         mt76x2u 2-2.4:1.0: vendor request req:47 off:9018 failed:-71
         mt76x2u 2-2.4:1.0: vendor request req:47 off:9018 failed:-71
         ...

It will continue to print more than 2000 times for about 5 minutes,
causing the usb device to be unable to be disconnected. During this
period, the usb port cannot recognize the new device because the old
device has not disconnected.

There may be other operating methods that cause -EPROTO, but -EPROTO is
a low-level hardware error. It is unwise to repeat vendor requests
expecting to read correct data. It is a better choice to treat -EPROTO
and -ENODEV the same way.

Similar to commit 9b0f100c1970 ("mt76: usb: process URBs with status
EPROTO properly") do no schedule rx_worker for urb marked with status
set  -EPROTO. I also reproduced this situation when plugging and
unplugging the device, and this patch is effective.

Just do not vendor request again for urb marked with status set -EPROTO.

Link: https://lore.kernel.org/all/531681bd-30f5-4a70-a156-bf8754b8e072@intel.com/
Link: https://lore.kernel.org/all/D4B9CC1FFC0CBAC3+20250105040607.154706-1-wangyuli@uniontech.com/
Fixes: b40b15e1521f ("mt76: add usb support to mt76 layer")
Co-developed-by: Xu Rao <raoxu@uniontech.com>
Signed-off-by: Xu Rao <raoxu@uniontech.com>
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Link: https://patch.msgid.link/9DD7DE7AAB497CB7+20250113070241.63590-1-wangyuli@uniontech.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>