cfg80211: drop duplicated documentation of field "probe_resp_offload"

The field "probe_resp_offload" was already documented above the
definition of struct wiphy. Both comments were identical.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200221115604.594035-1-Jerome.Pouiller@silabs.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>