deepin: kbuild: Reapply support for CONFIG_CC_OPTIMIZE_FOR_PERFORMANC…

[Avenger-285714]

…E_O3

1. Revert (a6036a4 "kbuild: drop support for CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3")
2. Mark -O3 as experimental, as it might cause unwanted regressions for users.
3. Allow all architectures to use the experimental -O3 optimization option. Previously, only ARC was allowed to use this option.

Link: https://lore.kernel.org/lkml/20191211104619.114557-1-oleksandr@redhat.com/

Link: https://lore.kernel.org/lkml/20220621133526.29662-1-mikoxyzzz@gmail.com/

[deepin-ci-robot]

deepin pr auto review

关键摘要:

• 在Makefile中新增的ifdef条件判断可能会导致KBUILD_CFLAGS和KBUILD_RUSTFLAGS的值在不同的编译选项下不一致，需要确保这一改动不会影响现有功能。
• 在init/Kconfig文件中新增的config CC_OPTIMIZE_FOR_PERFORMANCE_O3选项虽然提供了编译选项的灵活性，但应确保用户在尝试使用此选项时了解潜在的风险和后果。

是否建议立即修改:

• 是，建议立即检查Makefile和init/Kconfig文件中的改动，并确保它们不会引入新的问题或混淆。同时，应该提供足够的文档和警告信息，提醒用户在使用这些特殊编译选项时需要谨慎。

[deepin-ci-robot]

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