score: fix __get_user/get_user

commit c2f18fa4 upstream.

* should zero on any failure
* __get_user() should use __copy_from_user(), not copy_from_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>