Bluetooth: Update SCAN MODE state while turn OFF Bluetooth

Change will update SCAN MODE state while turn OFF Bluetooth, since
Bluetooth application is expecting adapterPropertyChangedCallback
while turning OFF BT. Otherwise, while Bluetooth is turning OFF
SET_SCAN_MODE_TIMEOUT occurs and application will not get proper
callback.

CRs-Fixed: 550485
Change-Id: I8bfdbdbf1962aff04cd7fdb4cee67d639bed8a38
(cherry picked from commit dbf81013f0f2b9dace2102d818284e9538dea4d9)
(cherry picked from commit 7e927547d91b6b0ff06dc36ae4436f32f9dc68c0)
(cherry picked from commit 00c4a408511c6ec92db09c4b5481e36ce615840d)