qcacmn: Allow simultaneous scans for Hostapd scan

Currently the drivers blocks every simultaneous scan
that comes to the driver, and returns BUSY.
here if the STA SCAN which is low priority after connection
comes, and at the same time ACS has completed and the hostapd
tries to do a HT scan, it would get error as BUSY, and it
will try to scan again and again until successful or the timeout
happens. This will in turn delay the hotspot bringup as start
ap does not come until the hostapd does a OBSS scan.

Fix is to skip the check of simultaneous scan for SAP, and make
the priority of scan request high for SAP scan.

Change-Id: I163dbb2fdca1245742cca049de47478117197412
CRs-Fixed: 2471897