The platform specific configuration(general_config) is optional.
However, the DVS settings should be configured explicitly while
loading the driver.
This patch enables configuring the default DVS mode even though
the platform data is not defined.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>