qcacld-3.0: Set neighbor scan channel max time to 40 msec as default

Currently, Driver has below configuration:
1. The default value of Neighbor scan channel max time = 30 msec
2. Probe deferral time = 15 msec and
3. The gap between each Probe Request (Probe repeat time) = 20 msec

As per above roam scan params, after 15 msec of deferral time STA
sends the first probe irrespective of OCE or non-OCE environment.
So after the first probe, STA never sends the second probe because
15 msec + 20 msec = 35 msec which is beyond dwell time( 30 msec).

Because of lower dwell time, many a time STA is not getting enough
time to send the second probe request during a roam scan on the currently
associated channel. In case when STA sends only one probe req,
there is a lesser chance to receive Probe Response in a semi congested
or congested environment. This results in not finding a candidate
during a roaming scan.

STA should have enough time to send 2 Probe Requests under any condition
( clean or noisy) irrespective of the OCE/non-OCE environment.

Fix is to increase the default value of dwell time
"gNeighborScanChannelMaxTime" to 40 msec for STA.

Change-Id: I1bd52f5efe448ccb4ed4585e98aaf519379dd661
CRs-Fixed: 2467703
1 file changed