nl80211: fix validation of scheduled scan info for wowlan netdetect

For wowlan netdetect a separate limit is defined for the number of
matchsets. Currently, this limit is ignored and the regular limit
for scheduled scan matchsets, ie. struct wiphy::max_match_sets, is
used for the net-detect case as well.

Cc: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>