habanalabs: Correct handling when failing to enqueue CB

The fence release flow is different if the CS was never submitted. In that
case, we don't have an hw_sob object attached that we need to "put". While
if the CS was aborted, we do need to "put" the hw_sob.

Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>