Epic: Support async signal handlers in Go static executables

[iapaddler]

Ref #508 and #667

[iapaddler]

Integrated with the internal libc. Latest on branch feat-internal-libc-dev.

• Disabled fs register switch in go_switch_thread()
• Ran terraform version 1.0.3 in a container (latest version is 1.17)
• This version of terraform uses panicwrap, which has the side affect of changing the argv list. In order to test signals and not deal with the argv array issue, the command line handling was hardcoded to make the command ldscope terraform -help work.
• Created a script that runs terraform help in a loop. This is the scenario where were able to see segfaults from async signal handlers previous to the use of an internal libc. Loop on this and check for errors in the return value:
  SCOPE_CRIBL_ENABLE=false ./ldscope terraform -help
• Previously we would see segfaults within <=100 times in this loop. The loop ran >20,000 times.
• Verified that this version of terraform uses Go 1.16 and we are getting events emitted.
• Verified that this version of terraform uses panicwrap: nm /bin/terraform | grep -i panicwrap
  0000000000409a00 T runtime.panicwrap
  000000000090e740 T github.com/mitchellh/panicwrap.Wrap
• FYI: the latest version of terraform uses Go 1.17 (likely 1.18 now). It appears from looking at source code that panicwrap is no longer used. We should test the argv list with Go 1.17+ support. Do we need to make changes to accommodate the argv list used here?