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.
Do not use just the driver name for this since driver_ndis.c supports
both wired and wireless NDIS drivers and needs to indicate the driver
type after initialization.