For dmaengine drivers which do not support transfer residue reporting we update
the PCM pointer with period granularity. Set the SNDRV_PCM_INFO_BATCH flag in
this case to let userspace know about this.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@linaro.org>