staging: rtl8188eu: remove duplicate if statement

There's two identical checks if the device was stopped or unplugged.
Remove one of them.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20210408195601.4762-10-martin@kaiser.cx


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>