perf test: Add a perf event fallback test

perf test: Add a perf event fallback test

This adds test cases to verify the precise ip fallback logic:

- If the system supports precise ip, for an event given with the maximum
  precision level, it should be able to decrease precise_ip to find a
  supported level.
- The same fallback behavior should also work in more complex scenarios,
  such as event groups or when PEBS is involved

Additional fallback tests, such as those covering missing feature cases,
can be added in the future.

Suggested-by: Ian Rogers <irogers@google.com>
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
Reviewed-by: Ian Rogers <irogers!@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>