radio: iris: Handle force close gracefully

- Whenever force closed, userspace state machine will not be available
  to handle the DISBALE event. Therefore during next turning ON operation,
  this event will be read and the FM never turns ON.
- Do not queue the FM disabled event while in OFF state.

Change-Id: I8f8cd31198f8bb1a7521920844e0f0c5c3190b08
CRs-Fixed: 492216
Signed-off-by: Venkateshwarlu Domakonda <Venkateshwarlu@codeaurora.org>