rtlwifi: Fix non-canonical address access issues

During realtek USB wireless NIC initialization, it's unexpected
disconnection will cause urb sumbmit fail. On the one hand,
_rtl_usb_cleanup_rx will be called to clean up rx stuff, especially for
rtl_wq. On the other hand, disconnection will cause rtl_usb_disconnect
and _rtl_usb_cleanup_rx to be called. So, rtl_wq will be flush/destroy
twice, which will cause non-canonical address 0xdead000000000122 access
and general protection fault.

Fixed this issue by remove _rtl_usb_cleanup_rx when urb sumbmit fail.

Signed-off-by: WeitaoWangoc <WeitaoWang-oc@zhaoxin.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1603768580-2798-1-git-send-email-WeitaoWang-oc@zhaoxin.com