SAE: Determine H2E vs. looping when restarting SAE auth in AP mode

SAE: Determine H2E vs. looping when restarting SAE auth in AP mode

If hostapd had existing STA SAE state, e.g., from a previously completed
SAE authentication, a new start of a separate SAE authentication (i.e.,
receiving of a new SAE commit) ended up using some of the previous
state. This is problematic for determining whether to H2E vs. looping
since the STA is allowed (even if not really expected to) to change
between these two alternatives. This could result in trying to use H2E
when STA was using looping to derive PWE and that would result in SAE
confirm failing.

Fix this by determining whether to use H2E or looping for the restarted
authentication based on the Status Code in the new SAE commit message
instead of previously cached state information.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>