qcacmn: Add support to restrict scan to preconfigured chans

Some times we need to scan only some pre configured
channels irrespective of channels requested in scan
start command.
Add support for pre specified list of scan channels
and scan only these channels if configured.

Change-Id: I7fa9ef9d626fd25d7855a7eb458818d8e2314fa5
CRs-Fixed: 2218494
3 files changed