The module unloading path had several problems:
- it freed up the private structure twice
- it freed up the codec structure, which was allocated as part
  of the private structure
- it did not freed up the reg_cache
- it did not unregistered the dais and the codec
Signed-off-by: NPeter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: NLiam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>