[FS#1123] base-files: os-release: HOME_URL not settable / set to LEDE_DEVICE_MANUFACTURER_URL

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Christian Schoenebeck (chris5560) 

Attached to Project - LEDE Project
Summary - base-files: os-release: HOME_URL not settable / set to LEDE_DEVICE_MANUFACTURER_URL
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Low
Priority - Very Low
Reported Version - All
Due in Version - Undecided
Due Date - Undecided
Details - Device independent
LEDE 17.01.4 and LEDE r5201-8b9cdebc9c

Set
-> Image configuration
-> Version configuration options
-> Manufacturer URL
to a non-empty value and build

Problem:
  - HOME_URL set to LEDE_DEVICE_MANUFACTURER_URL
  - HOME_URL is nowhere settable inside “make menuconfig”
  - If Manufacturer URL is cleared, HOME_URL still set after rebuild

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=1123