Initial groundwork for VLAN controller

[tchinmai7]

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

TODOs:

• squashed commits
• includes documentation
• adds unit tests
• adds or updates e2e tests

[codecov]

Codecov Report

Attention: Patch coverage is 9.80392% with 92 lines in your changes missing coverage. Please review.

Project coverage is 64.15%. Comparing base (01bf52a) to head (14bb6c1).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
controller/linodemachine_controller_helpers.go	9.41%	74 Missing and 3 partials ⚠️
controller/linodecluster_controller.go	0.00%	9 Missing and 1 partial ⚠️
api/v1alpha2/linodecluster_webhook.go	0.00%	4 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #525      +/-   ##
==========================================
- Coverage   65.50%   64.15%   -1.35%     
==========================================
  Files          78       78              
  Lines        4090     4182      +92     
==========================================
+ Hits         2679     2683       +4     
- Misses       1167     1251      +84     
- Partials      244      248       +4     

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[AshleyDumaine]

For this to work we will need this PR merged, a release for the CCM cut, and the CCM version bumped here, otherwise external IPs will not get set on the Nodes.