P2P: Allow wpa_supplicant to start if social channels are not supported

P2P: Allow wpa_supplicant to start if social channels are not supported

It was possible for an nl80211-based driver to be determined to support
P2P even when the radio supports only the 5 GHz band. This resulted in
P2P initialization failing due to not being able to pick a social
channel and wpa_supplicant not starting. Fix this by not enabling P2P,
but still allowing wpa_supplicant initialization to complete.

Signed-off-by: Jouni Malinen <j@w1.fi>