perf intel-pt: Fix error timestamp setting on the decoder error path

An error timestamp shows the last known timestamp for the queue, but this
is not updated on the error path. Fix by setting it.

Fixes: f4aa0819

 ("perf tools: Add Intel PT decoder")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-8-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>