qcacld-3.0: Check for valid vdev_id in wma_is_roam_in_progress
When kickout event is received from firmware, the function
wma_is_roam_in_progress is called to check the roaming in
progress using vdev_id .
Vdev_id needs to be checked for valid vdev_id prior to
derefencing it.
Change-Id: Ib56895ad73b5dcefe7a0b9f65089306bf42d78eb
CRs-Fixed: 3020665