ASoC: codecs: Add missing control_type initialization

Some codec drivers do not initialize the control_type field in their private
device struct, but still use it when calling snd_soc_codec_set_cache_io.
This patch fixes the issue by properly initializing it in the drivers probe
functions.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org (for 2.6.37 only)