Bug#505789: Fix confirmation

[Jurij Smakov <jurij@wooyd.org>]

Hi,

I've just confirmed using the daily build netinst that getting 
firmware file from a USB stick works.

Thanks.
-- 
Jurij Smakov                                           jurij@wooyd.org
Key: http://www.wooyd.org/pgpkey/                      KeyID: C99E03CC