wlcore: support scan reports during periodic scan

FW API changed and now PERIODIC_SCAN_REPORT_EVENT is sent
in case results were found at the end of each sched scan
cycle. Previous FW was missing that and broke sched scan.

This API change is available from 18xx FW 8.5.0.0.27

[Arik - move changes to 18xx specific files, align FW structures to
latest for scan command]

Signed-off-by: Eyal Shapira <eyal@wizery.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>