rustbuild: Remove Mode::Codegen

[petrochenkov]

It's no longer used.

[rust-highfive]

r? @Mark-Simulacrum

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[Mark-Simulacrum]

@bors r+ rollup

[bors]

📌 Commit 4fff14d has been approved by Mark-Simulacrum

[bors]

⌛ Testing commit 4fff14d with merge 02cbead55f3c221ef6ad402bb475dd4cde67ef48...

[rust-log-analyzer]

The job mingw-check of your PR failed (pretty log, raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

Build completed successfully in 0:02:00
+ /scripts/validate-toolstate.sh
Cloning into 'rust-toolstate'...
<Nothing changed>
HTTPError: HTTP Error 403: Forbidden
b'{"message":"API rate limit exceeded for user ID 7378925.","documentation_url":"https://docs.github.com/rest/overview/resources-in-the-rest-api#rate-limiting"}'
Traceback (most recent call last):
  File "../../src/tools/publish_toolstate.py", line 288, in <module>
    validate_maintainers(repo, github_token)
  File "../../src/tools/publish_toolstate.py", line 84, in validate_maintainers
    'Accept': 'application/vnd.github.hellcat-preview+json',
  File "/usr/lib/python3.6/urllib/request.py", line 223, in urlopen
    return opener.open(url, data, timeout)
  File "/usr/lib/python3.6/urllib/request.py", line 532, in open
    response = meth(req, response)
  File "/usr/lib/python3.6/urllib/request.py", line 642, in http_response
    'http', request, response, code, msg, hdrs)
  File "/usr/lib/python3.6/urllib/request.py", line 570, in error
    return self._call_chain(*args)
  File "/usr/lib/python3.6/urllib/request.py", line 504, in _call_chain
    result = func(*args)
  File "/usr/lib/python3.6/urllib/request.py", line 650, in http_error_default
    raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 403: Forbidden
  local time: Mon Sep  7 08:57:56 UTC 2020
  network time: Mon, 07 Sep 2020 08:57:56 GMT
== end clock drift check ==
== end clock drift check ==
##[error]Process completed with exit code 1.
Terminate orphan process: pid (4349) (node)
Terminate orphan process: pid (4358) (python)

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @rust-lang/infra. (Feature Requests)

[bors]

💔 Test failed - checks-actions

[petrochenkov]

2020-09-07T08:57:56.6359908Z HTTPError: HTTP Error 403: Forbidden
2020-09-07T08:57:56.6361177Z b'{"message":"API rate limit exceeded for user ID 7378925.","documentation_url":"https://docs.github.com/rest/overview/resources-in-the-rest-api#rate-limiting"}'

@bors retry