ASoC: Instantiate any forgotten DAPM widgets

With the recent changes to the DAPM power checks it has become important
to explicitly instantiate all widgets but some drivers were forgetting
to do that.  Since everything needs to do it add a call to instantiate
them immediately before the card registration - it does no harm when it
is called repeatedly and saves work in drivers.

Tested-by: pHilipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>