[Buildroot] [PATCH] merge_config.sh: Fix merging buildroot config files

[Petr Vorel]

Hi Arnout,

> > Removing unset will cause the following make command work wrong. Note
> > that the value of this environment variable is checked [1] and used. The
> > result of removing the unset line is that we will have double BR2_
> > prefixes in the final .config file as well as lots of warnings when
> > checking if all specified config values have been taken.

>  We have no prefix, the BR2_ is mere convention. So when calling merge_config,
> we should set CONFIG_ to empty, not to BR2_.

>  So indeed, the unset should be removed.

+1. I overlooked that regexp works with empty $CONFIG_ as well.
Thanks for explanation.

Kind regards,
Petr