Add changes to handle transition to the 2 new states:
1. Roaming in progress: Switch to this state when roam
start notification is received from firmware.
2. Roam Synch in progress: Switch to this from RSO
STARTED state if roam synch indication event is received
from firmware. Change to this state is also allowed in
RSO STOPPED state if supplicant disabled roaming on that
vdev - to allow roam invoke to be processed.
Also query the state machine to get the roaming status instead
of using discrete flags at various layers. Clean the redundant
roaming in progress, roam synch related flags.
Change-Id: Ide20a30d9d8c20a96d8bba70367b51b8643cae09
CRs-Fixed: 2725443
eb128b5dfe