ASoC: optimize init sequence of Freescale MPC8610 sound drivers

ASoC: optimize init sequence of Freescale MPC8610 sound drivers

In the Freescale MPC8610 sound drivers, relocate all code from the _prepare
functions into the corresponding _hw_params functions.  These drivers assumed
that the sample size is known in the _prepare function and not in the
_hw_params function, but this is not true.

Move the code in fsl_dma_prepare() into fsl_dma_hw_param().  Create
fsl_ssi_hw_params() and move the code from fsl_ssi_prepare() into it.

Turn off snooping for DMA operations to/from I/O registers, since that's not
necessary.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>