stm class: Update documentation to match the new identification rules

The rules and order of identification of trace sources against the
"stp-policy" have changed; update the documentation to reflect that.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed