Simpleperf: remove dependency on global current_arch.
When running unit tests on arm64 devices:
ERROR: can't unwind data recorded on a different architecture.
It is because ReportCommandtest.dwarf_callgraph opens a perf.data
recorded on x86_64, and changes current_arch. It causes a problem when
the test record_cmd.dwarf_callchain_sampling calls libbacktrace built
on aarch64. Athough it doesn't make the test fail, we should fix this.
10 files changed