simpleperf: fix test record_cmd.duration_option.

The test should write perf.data to a temporary file, because
the test may not have permission to write perf.data in
current directory.

Bug: http://b/30405638
Change-Id: Iff4ac7ea014f29e58146ad79c8dc3b0abcdb8d41
Test: run simpleperf_unit_test.
1 file changed