ASoC: SMDK64XX: Rename for other platforms

We plan to use the same ASoC Machine driver for most of
latest SMDK platforms. So rename the 64XX specific driver
to generic named.

Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>