ieee80211softmac_auth_resp() fix

The struct ieee8021_auth * passed to it comes straight from skb->data
without any conversions; members of the struct are little-endian, so
we'd better take that into account when doing switch by auth->algorithm,
etc.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>