wlantest: Fix handling of PTK rekeying

wlantest: Fix handling of PTK rekeying

Use a temporary PTK buffer during 4-way handshake when rekeying PTK
so that the new EAPOL-Key frame MIC values are checked against the
new PTK and frames are decrypted using the old PTK. Take the new
PTK into use once msg 4/4 is processed and clear RSC counters at
that point (including moving of RSC update to avoid setting RSC
based on the msg 4/4).

In addition, add a workaround to handle supplicant implementations that
set Secure bit to one during PTK rekeying 4-way handshake in msg 2/4.
This was previously assumed to be msg 4/4, but the key data contents
can be used to figure out whether this is msg 2/4 even if the Secure
bit is set to one.

Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>