When STA+SAP is operating in indoor channels, mandatory
channel list is added to the supported channel list of the
seconday interface.
But the API is common even for SAP+SAP and fails to detect
interfering channels in case of SAP+SAP due to this.
So, limit the mandatory channel list consideration only
for STA+SAP.
Change-Id: If7063e81d0daa9ef86b8af71ba517756f96edb32
CRs-Fixed: 3245034