src.ctf.lttng-live: remove unnecessary assignment in lttng_live_iterator_handle_new_s...

src.ctf.lttng-live: remove unnecessary assignment in lttng_live_iterator_handle_new_streams_and_metadata

Fix this clang-tidy warning:

    /home/simark/src/babeltrace/src/plugins/ctf/lttng-live/lttng-live.cpp:612:13: warning: Value stored to 'status' is never read [clang-analyzer-deadcode.DeadStores]
                status = LTTNG_LIVE_ITERATOR_STATUS_OK;
                ^        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This value is indeed always overwritten in any case, in the if at the
end of the function.

Change-Id: I1899d07f389ae32abda34218b452d93d6d6a092b
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/7186
Tested-by: jenkins <jenkins@lttng.org>
Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>