Fix `run.sh` and `run_traces.sh` trace path handling by taking into
account that the `--trace` option may contain a multi-directory path
relative to traces-db.
Together with this fix, you should expect to find the output directory
of a perf testing session under the same directory of the trace file.
Signed-off-by: Antonio Caggiano <antonio.caggiano@collabora.com>
Reviewed-by: Gert Wollny <gert.wollny@collabora.com>