Revert "ASoC: AC97 doesn't use regmap by default"

Since commit 98d3088e (SoC: core: Fix check before defaulting to regmap)
, it is not necessary to provide codec->control_data anymore.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>