Extend the perf branch sorting code to support sorting by in_tx
or abort_tx qualifiers. Also print out those qualifiers.

This also fixes up some of the existing sort key documentation.

We do not support no_tx here, because it's simply not showing
the in_tx flag.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-4-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>