Unlike the Time Profiler, the CPU Profiler in Instruments use `cycles` for units instead of `ms`:
<img width="872" src="https://user-images.githubusercontent.com/406394/175755999-289cb7c0-f29a-44b1-b00e-b55ef17ee303.png">
Currently Speedscope fails to import the data with the following error in the console:
```
Failed to load format Error: Unrecognized units Gc
```
This PR adds support for `cycles` as a unit to the Instruments deep copy importer as well as `Kc`, `Mc`, and `Gc`, which I'm assuming are increasing in multiples of 1000. Hopefully I've added support for this correctly and this PR is helpful.
