## Bootmagic Deprecation and Refactor ([#12172](https://github.com/qmk/qmk_firmware/pull/12172))

QMK has decided to deprecate the full Bootmagic feature and leave Bootmagic Lite as the only remaining option.

This pull request changes the behavior of `BOOTMAGIC_ENABLE` such that specifying `BOOTMAGIC_ENABLE = yes` enables Bootmagic Lite instead of full Bootmagic.

### Tentative Deprecation Schedule

This is the current planned roadmap for the behavior of `BOOTMAGIC_ENABLE`:

- From 2021-05-29, setting `BOOTMAGIC_ENABLE = yes` will enable Bootmagic Lite instead of full Bootmagic.
- From 2021-08-28, `BOOTMAGIC_ENABLE` must be either `yes`, `lite`, or `no` – setting `BOOTMAGIC_ENABLE = full` will cause compilation to fail.
- From 2021-11-27, `BOOTMAGIC_ENABLE` must be either `yes` or `no` – setting `BOOTMAGIC_ENABLE = lite` will cause compilation to fail.
