cli: improve error logging in set_stream_intersections

cli: improve error logging in set_stream_intersections

I experienced some errors in set_stream_intersections, and found the
error messages to be very generic and non-helpful.  This patch makes the
function use BT_CLI_LOGE_APPEND_CAUSE when possible and produce more
precise error messages.

Change-Id: I4db2859f8f76de95de12c4139c621b068e22d3ba
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/2003
Tested-by: jenkins <jenkins@lttng.org>
Reviewed-by: Francis Deslauriers <francis.deslauriers@efficios.com>