[Buildroot] [PATCH v2] Extend and use the <pkg>_CONFIG_FIXUP infra

[Thomas Petazzoni]

Hello,

Here is a new version of the "Extend and use the <pkg>_CONFIG_FIXUP
infra" patch series. Compared to the previous version:

 * Fix the documentation as suggested by Arnout (don't mention details
   related to deprecated features)
 * Added Acked-by from Arnout and/or Samuel where appropriate.

Thanks,

Thomas