perf scripts python: Support syscall name parsing on arm64

In the result of "perf script syscall-counts" on arm64, the syscall
events are not resolved currently. Add "aarch64" to audit uname list to
support name parsing.

* After the patch:

  [root@localhost ~]# perf script syscall-counts sleep 1
  Press control+C to stop and show the summary

  syscall events:

  event                                          count
  ----------------------------------------  -----------
  mmap                                               6
  close                                              5
  mprotect                                           4
  brk                                                3
  newfstatat                                         3
  openat                                             3
  getrandom                                          1
  prlimit64                                          1
  munmap                                             1
  clock_nanosleep                                    1
  set_robust_list                                    1
  set_tid_address                                    1
  exit_group                                         1
  read                                               1
  faccessat                                          1

Signed-off-by: Wei Li <liwei391@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230815131735.1237221-1-liwei391@huawei.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>