previously in this function:

u32 index = (dwrq->flags & IW_ENCODE_INDEX) - 1;

index is unsigned, so if -1, the original test (below) didn't work.
Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: John W. Linville <linville@tuxdriver.com>