qcacmn: dont send Spectral stop WMI if Spectral scan is not in progress

Before sending Spectral stop WMI to FW check whether Spectral
scan is in progress. When all vdevs are in down state host driver
will send a stop Spectral scan command to FW. In that scenario there
is a possibility that stop Spectral scan WMI message may go to FW
even though Spectral scan is not active. To prevent this we add a check
in stop Spectral scan routine to send WMI message only if
scan is in progress.

CRs-Fixed: 2424020
Change-Id: I2119935759c40f62df75574b6a29174973f2703f
1 file changed