Use a parameter structure to pass in information that can be more easily
extended in the future. Include some of the parameters that were
previously read directly from hapd->conf in order to reduce need for
including hostapd/config.h into driver wrappers.
This commit merges the driver_ops structures and implementations from
hostapd/driver*.[ch] into src/drivers. This is only an initial step and
there is room for number of cleanups to share code between the hostapd
and wpa_supplicant parts of the wrappers to avoid unnecessary source
code duplication.
