Investigate missing Go stack entries

[kakkoyun]

If there are go runtime stack entries, such as runtime.mstart or runtime.sysmon, then this is the Linux Kernel walking the go runtime stack too far.

Originally posted by @brancz in https://github.com/parca-dev/parca.dev/pull/24#discussion_r724187974

[javierhonduco]

Is this issue still present?

[kakkoyun]

Is this issue still present?

I need to double-check.

[brancz]

We fixed this at some point! This was the fp unwinder going further than the bottom of the stack.