staging: rtl8712: Coding style: Fix missing spaces

* Add missing spaces around bitwise OR operation in order to get
  rid of checkpatch.pl's "CHECK: spaces preferred around that '|'"

Signed-off-by: Michael Hornung <mhornung.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>