qcacmn: Remove redundant check in wlan_scan_start
In api wlan_scan_start(), redundant check for
scan_start_req is observed in some static analysis
tool.
Remove the redundant check in the ap
wlan_scan_start() as the check is present in the
api scm_scan_free_scan_request_mem
Change-Id: Ic320bb95253668310c5d738216daba62ba2f4b3f
CRs-Fixed: 3528505