rndis_wlan: set cipher suites for cfg80211

rndis_wlan does not set cipher suites list for cfg80211 which causes
wext-compat-range to report rndis_wlan not supporting WPA. Patch adds
cipher suites list and fixes NetworkManager not being able to connect to
WPA encrypted APs.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>