ESP-IDF allows projects to specify a sdkconfig.defaults values which contain
preset values for configuration options of relevance to the project. This
allows ESP-IDF to use those presets while supplying default values for all
other configuration options, when generting the final sdkconfig file.
Changes:
- Ran `idf.py save-defconfig` to find non-default value configs. Saved
relevant ones to `sdkconfig.defaults`
- Removed `sdkconfig` file
- Added `sdkconfig` to `.gitignore` as ESP-IDF will generate a `sdkconfig`
based on `sdkconfig.defaults` when building.
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