releasetools: Remove dead functions in EdifyGenerator.

Remove the following functions that are needed for file-based OTAs only:
 - SetPermissions()
 - SetPermissionsRecursive()
 - MakeSymlinks()
 - DeleteFiles()
 - DeleteFilesIfNotMatching()
 - RenameFiles()
 - SkipNextActionIfTargetExists()

Bug: 35853185
Test: Verified there's no reference to these functions.
Change-Id: Iff24a9d705476211effaef28eed2a147fa5fcbce
2 files changed