intel_th: msu: Make contiguous buffers uncached

We already keep the multiblock mode buffers uncached, but forget the
single mode. Address this.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20210621151246.31891-4-alexander.shishkin@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>