ath5k: temporarily disable crypto for AP mode

Pavel Roskin reported some issues with using AP mode without
nohwcrypt=1.  Most likely this is similar to the problem fixed
some time ago in ath9k by 3f53dd64

,
"ath9k: Fix hw crypto configuration for TKIP in AP mode."

That only affects TKIP but it's easiest to just disable that and
WEP too until we get a proper fix in.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>