Staging: rtl8192u: Remove else after return

This patch simplifies the code by removing else and fixes
the following checkpatch.pl warning: "else is not useful after
break or return".

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>