[FS#291] Predefined config files at <buildroot>/files directory not copy to the router image

[LEDE Bugs]

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FS#291 - Predefined config files at /files directory not copy to the router image 
User who did this: Jo-Philipp Wich (jow-)
Status: Unconfirmed -> Waiting on reporter

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=291