[PATCH] hostap: Do not free local->hw_priv before unregistering netdev

local->hw_priv was being freed and set to NULL just before calling
prism2_free_local_data(). However, this may expose a race condition in
which something ends up trying to use hw_priv during shutdown. I
haven't noticed this happening, but better be safe than sorry, so
let's postpone hw_priv freeing to happen only after
prism2_free_local_data() has returned.

Signed-off-by: Jouni Malinen <jkmaline@cc.hut.fi>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>