tmf: Fix trace properties not shown when location URI has encoded chars

tmf: Fix trace properties not shown when location URI has encoded chars

The trace properties (e.g. CTF environment variables) are not shown when
the trace element's location URI contains encoded characters (e.g.
space=%20), because the trace path uses the decoded characters and
therefore does not match the trace element's location.

The patch also modifies the output of the 'location' property to show
the unencoded URI string.

Change-Id: Ida0c56096b88690058eccfc5e408222fd461f7b7
Signed-off-by: Patrick Tasse <patrick.tasse@gmail.com>
Reviewed-on: https://git.eclipse.org/r/24022
Tested-by: Hudson CI
Reviewed-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
IP-Clean: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
Tested-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>