Merge ~smoser/cloud-init:fix/1787459-fix-ds-sys_cfg into cloud-init:master

[Scott Moser]

stages: Fix bug causing datasource to have incorrect sys_cfg.

The Init object had a bug/odd side effect where when retrieving a distro
object it would update the datasources's sys_cfg. That was probably
intended to refresh the possibly stale config stored there. Unfortunately
what it actually did limit the config there to the 'system_info' top level
key where initially it had the whole config.

LP: #1787459

see commit message

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:f31ece7f0c6178fbc803e44dfe95c18566e10594
https://jenkins.ubuntu.com/server/job/cloud-init-ci/325/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    IN_PROGRESS: Declarative: Post Actions

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review: Approve (continuous-integration)

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:e8a296c5f67aee22256a78361053acf186ca6a14
https://jenkins.ubuntu.com/server/job/cloud-init-ci/326/
Executed test runs:
    FAILED: Checkout

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review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:e8a296c5f67aee22256a78361053acf186ca6a14
https://jenkins.ubuntu.com/server/job/cloud-init-ci/330/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    IN_PROGRESS: Declarative: Post Actions

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/cloud-init-ci/330/rebuild

review: Approve (continuous-integration)

[Chad Smith (chad.smith)]

review: Needs Fixing

[Scott Moser (smoser)]

addressed chad's feedback.

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:1fe8b60c1d6ff35620c212957aed62bee77ac589
https://jenkins.ubuntu.com/server/job/cloud-init-ci/335/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    IN_PROGRESS: Declarative: Post Actions

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/cloud-init-ci/335/rebuild

review: Approve (continuous-integration)

[Chad Smith (chad.smith)]

THANKS LGTM

review: Approve

[Server Team CI bot (server-team-bot)]

FAILED: Autolanding.
More details in the following jenkins job:
https://jenkins.ubuntu.com/server/job/cloud-init-autoland-test/63/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    FAILED: Ubuntu LTS: Integration

review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

review: Approve (continuous-integration)

diff --git a/cloudinit/stages.py b/cloudinit/stages.py
index ef5c699..8a06412 100644
--- a/cloudinit/stages.py
+++ b/cloudinit/stages.py
@@ -88,7 +88,7 @@ class Init(object):
             # from whatever it was to a new set...
             if self.datasource is not NULL_DATA_SOURCE:
                 self.datasource.distro = self._distro
-                self.datasource.sys_cfg = system_config
+                self.datasource.sys_cfg = self.cfg
         return self._distro
 
     @property