drivers: dma: intel-adsp-hda: add a missing "break"

A "switch" statement in intel_adsp_hda_dma_status() seems to be
missing a "break". The second "break" is unneeded but seems to be a
part of the coding style.

Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>