qcacld-3.0: Avoid VDEV start for new interface when roaming in progress

Currently driver allows start_bss on SAP interface even when roaming is
in progress on STA interface. This leads to two simultaneous vdev starts
in FW which causes the FW to assert.

Add changes to reject the start_bss request for SAP if roaming is in
progress on any STA interface.
Also, when a connect for STA or start_bss for SAP is received and
roaming is not in progress for any STA interface, stop roaming on all
STA interfaces by sending WMI_ROAM_SCAN_MODE_NONE to FW. Also after
association or start_bss completion, enable roaming again on connected
STA interface.

Change-Id: I3baaffeef3b350e6527660cbac4b79fa4d9f83f0
CRs-Fixed: 2221337
11 files changed