802.11i-2004 did not specify that RSN can be added to the probereq,
only to the proberesp (and others) yet it was added in what seems was
b032f27c365b992e9d8e42214183b39acfb8c6ac (multi-BSS support).
802.11-2020 does not list the IE either for probereq so remove it.
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