qcacmn: Follow spec for NL80211_CMD_START_SCHED_SCAN
qcacld-2.0 to qca-wifi-host-cmn propagation
If no SSID are passed to NL80211_CMD_START_SCHED_SCAN cmd,
interface spec requires that an active scan is not needed.
Therefore a passive scan is now requested by cfg80211_sched_scan_request
for this case.
Change-Id: I1b1b9232ffb9d8d5c0bc9a1d75145d39c9fe9e6b
CRs-Fixed: 902092