perf db-export: No need to pass thread twice to db_export__sample

perf db-export: No need to pass thread twice to db_export__sample

As it is available via another parameter, address_location->thread.

Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: lkml.kernel.org/r/551D08F8.3040706@intel.com
Link: http://lkml.kernel.org/n/tip-6dbn0tcm9hyv92g7h3zj2dbt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>