init darwin cpu support

[pixelsoccupied]

init darwin cpu support! Dev/ran on M1 Max and manually tested the sysctl commands on intel

Thanks!

[jaypipes]

@pixelsoccupied awesome first stab at this, thank you so much for the PR! :)

I've left a few requests inline for you to chew on. Lemme know if any of my feedback doesn't make sense.

Best,
-jay

[leaanthony]

Bump 😄

[pixelsoccupied]

@jaypipes ready for a final review. This how it looks like if I run the exact code from readme's example

cpu (2 physical packages, 10 cores, 10 hardware threads)
 physical package #0 (8 cores, 0 hardware threads)
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  capabilities: [FEAT_PMULL FEAT_LSE FEAT_SHA1 FEAT_CSV2 FEAT_CSV3 FEAT_FHM
                 FEAT_FlagM2 FEAT_SHA256 FEAT_FP16 FEAT_SHA512 FEAT_PAuth FEAT_DIT
                 FEAT_SSBS FEAT_DPB2 FEAT_FlagM FEAT_RDM FEAT_FCMA FEAT_AES
                 FP_SyncExceptions FEAT_LRCPC FEAT_DPB FEAT_SB FEAT_SHA3 armv8_crc32
                 AdvSIMD_HPFPCvt AdvSIMD floatingpoint]
 physical package #0 (2 cores, 0 hardware threads)
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  <nil>
  capabilities: [armv8_crc32 AdvSIMD_HPFPCvt FEAT_DotProd FEAT_JSCVT FEAT_FRINTTS FEAT_LRCPC2
                 FEAT_LSE2 FEAT_PMULL FEAT_SHA1 FEAT_LSE FEAT_CSV2 FEAT_CSV3
                 FEAT_FHM FEAT_FlagM2 FEAT_SHA256 FEAT_FP16 FEAT_SHA512 FEAT_PAuth
                 FEAT_DIT FEAT_SSBS FEAT_DPB2 FEAT_FlagM FEAT_RDM FEAT_FCMA
                 FEAT_AES AdvSIMD floatingpoint]

And of course some nice info drill down a bit more (a debug screenshot from previous comment)