cfg80211: allow vendor commands to be sent to nan interface

Allow vendor commands that require WIPHY_VENDOR_CMD_NEED_RUNNING flag
to be sent to NAN interface.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>