update defaults

  * Add static files list, for offline build
  * Unhardcode mcp_static_images_url
  * Unhardcode salt_control_*_image

Change-Id: Ia774d16a0f34362535d4f91d3add47b8ecebf7c1
Prod-related: PROD-26662 (PROD:26662)
(cherry picked from commit 5adb88c335f650b058151a9542be545a83e75709)
3 files changed