staging: rtl8192u: add spaces around '=', '+=', '<', '||'

This fixes the checkpatch.pl errors:
ERROR: spaces required around that '=' (ctx:VxV)
ERROR: spaces required around that '+=' (ctx:VxV)
ERROR: spaces required around that '<' (ctx:VxV)
ERROR: spaces required around that '||' (ctx:VxE)

Signed-off-by: Roxana Blaj <roxanagabriela10@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>