qcacld-3.0: Stop opportunistic timer for NAN cmds in HL platforms

Opportunistic timer gets triggered as soon as a DBS use case
is completed and hw_mode would be set to SMM when the
timer(5 seconds) expires.
Below is an example scenario,
1. DBS is enabled to support STA on 5GHz + SAP on 2.4GHz on
   a Helium device.
2. SAP is disabled(to enable NAN as NAN+SAP is not supported on
   HL platforms)
3. Opportunistic timer gets triggered with a timeout of 5 seconds
   as DBS is not needed anymore.
4. Once the timer expires, WMI_PDEV_SET_HW_MODE_CMDID command
   would be sent to firmware to set the hw_mode to SMM.

But if framework enables NAN immediately after disabling SAP,
firmware can't allow it as NAN is not supported in DBS mode in
Helium platforms. Thereby firmware either rejects the NAN enable
or defer it till set_hw_mode command is received(which introduces
a delay of 5 seconds as host sends it after timer expiry).

So, stop the timer and complete corresponding action when a NAN
command is received from framework to avoid this failure/delay.

Change-Id: I50521c0dd5f2314034957a0f65898c737cfe7e2e
CRs-Fixed: 2937407