libm: Run benchmarks on aarch64 as well as x86-64

[tgross35]

No description provided.

[tgross35]

There must be a quiet error accessing perf counters or something. On CI results are looking like this:

icount::icount_bench_acos_group::icount_bench_acos logspace:setup_acos()
  Baselines:                      softfloat|softfloat
  Instructions:                          42|N/A                  (*********)
  L1 Hits:                               50|N/A                  (*********)
  L2 Hits:                                1|N/A                  (*********)
  RAM Hits:                               8|N/A                  (*********)
  Total read+write:                      59|N/A                  (*********)
  Estimated Cycles:                     335|N/A                  (*********)

But locally, something like this should be more accurate:

icount::icount_bench_acos_group::icount_bench_acos logspace:setup_acos()
  Instructions:                       11705|N/A                  (*********)
  L1 Hits:                            13028|N/A                  (*********)
  L2 Hits:                                1|N/A                  (*********)
  RAM Hits:                              17|N/A                  (*********)
  Total read+write:                   13046|N/A                  (*********)
  Estimated Cycles:                   13628|N/A                  (*********)

[tgross35]

I don't think this will work, maybe in qemu.

[tgross35]

Turned some of this into #933