Request: Save the config used for prebuilt kernels to e.g. extra/config

[tc287]

While it's possible to find the config used for each kernel version with .../extract-ikconfig modules/5.10.74+/kernel/kernel/configs.ko, it seems like it would be easier to view (and view diffs) if the .config was saved as text.

I suggest extra/{config,config7,config7l,config8}, for consistency with the other files in extra/ while (hopefully) avoiding confusion with /boot/config.txt. Another option might be kernel{,7,7l,8}.config, or perhaps .config{,7,7l,8} if you don't mind dotfiles (and I don't think the ".config" name is usually used outside of the kernel source tree, or something based on one such as a linux-headers package).

[pelwell]

1. The config file isn't useful without a kernel tree.
2. The kernel tree contains all the defconfig files used to generate all the config files used to build all our kernels - we never add or remove settings except via the defconfigs.
3. The file extra/git_hash in this repo contains the Linux repo hash that was used to build the kernels in that release.

Given those points it would only take a very simple script to create the config for any kernel in any firmware release.