Module unload is getting trigered in between
Vap restart due to channel switch
while waiting in monitor module unload for 500ms VAPs are coming up.
And after wait, during monitor pdev deinit
HOST start receiving stats indication.
Monitor pdev is getting dettached while processing stats indication.
Move register/derester of stats handler to intr ops.
Change-Id: I821c144f54bfe78c567039ab57fcf1eac7cb4f46
CRs-Fixed: 3192980