perf probe-file: Delete namelist in del_events() on the error path

perf probe-file: Delete namelist in del_events() on the error path

ASan reports some memory leaks when running:

  # perf test "42: BPF filter"

This second leak is caused by a strlist not being dellocated on error
inside probe_file__del_events.

This patch adds a goto label before the deallocation and makes the error
path jump to it.

Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Fixes: e7895e422e4da63d ("perf probe: Split del_perf_probe_events()")
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/174963c587ae77fa108af794669998e4ae558338.1626343282.git.rickyman7@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>