x86 arch provides the testing for conversion between tsc and perf time,
the testing is located in x86 arch folder.  Move this testing out from
x86 arch folder and place it into the common testing folder, so allows
to execute tsc testing on other architectures (e.g. Arm64).

This patch removes the inclusion of "arch-tests.h" from the testing
code, this can avoid building failure if any arch has no this header
file.

Committer testing:

  $ perf test -v tsc
  Couldn't bump rlimit(MEMLOCK), failures may take place when creating BPF maps, etc
  70: Convert perf time to TSC                                        :
  --- start ---
  test child forked, pid 4032834
  mmap size 528384B
  1st event perf time 165409788843605 tsc 336578703793868
  rdtsc          time 165409788854986 tsc 336578703837038
  2nd event perf time 165409788855487 tsc 336578703838935
  test child finished with 0
  ---- end ----
  Convert perf time to TSC: Ok
  $
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/r/20201019100236.23675-2-leo.yan@linaro.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>