Cleanup path-mapping enablement (#4441)

**What type of PR is this?**
code cleanup

**What does this PR do? Why is it needed?**
This enables path-mapping for the GoInfo action and simplifies the
`builder_args`. As a side effect, we now set the `-goroot` flag for link
actions but they do not yet opt into path mapping (and I don't think
they will work yet, since they use .path on the archives)

**Which issues(s) does this PR fix?**

Fixes #

**Other notes for review**
8 files changed