Staging: rt3090: Fix RT3090 scan AP function

Fix RT3090 scan AP function.

This patch fixes the rt3090 wireless module failed
to scan AP around due to  Windows driver causing
rt3090 module unable to scan AP in Linux.

Acked-by: Lee, Chun-Yi <jlee@novell.com>
Signed-off-by: Chen, Chien-Chia <machen@novell.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>