perf test: Convert watch point tests to test cases.

perf test: Convert watch point tests to test cases.

Use null terminated array of test cases rather than the previous sub
test functions.

Committer notes:

On s/390x we don't use __event(), so wrap it with __s390x__

Signed-off-by: Ian Rogers <[email protected]>
Tested-by: Sohaib Mohamed <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Brendan Higgins <[email protected]>
Cc: Daniel Latypov <[email protected]>
Cc: David Gow <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jin Yao <[email protected]>
Cc: John Garry <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Paul Clarke <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>