stm class/intel_th: Updates for v5.5

These are:
 * a bugfix in stm protocol handling
 * a documentation update for intel_th
intel_th: Document software sinks

Add documentation for the software sinks API of the MSU driver and the
msu-sink module in particular.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
1 file changed