Prepare hwsim Extended Key ID support for a mac80211 API change.

The mac80211 flag IEEE80211_HW_EXT_KEY_ID_NATIVE is being replaced by
NL80211_EXT_FEATURE_EXT_KEY_ID which only must be set by drivers when
they support HW crypto.

This reverts commit cfe7007a ("mac80211_hwsim: Extended Key ID support").
Signed-off-by: NAlexander Wetzel <alexander@wetzel-home.de>
Link: https://lore.kernel.org/r/20190629195015.19680-1-alexander@wetzel-home.deSigned-off-by: NJohannes Berg <johannes.berg@intel.com>