Tests: Add and set new log-file-d for the tap driver

Tests: Add and set new log-file-d for the tap driver

This adds a new option `--log-file-d` to the tap-driver, which will
create a `*.log.d` folder for each test when running `make check` and
the `LTTNG_TEST_LOG_DIR` accordingly.

Doing so allows the tests to be run in verbose and create logs in a
predictable location. These log folders are removed when running `make
clean`.

Change-Id: Ibcf7e2cb54098a3e9ccd828ca76df6efcf33431d
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>