docs/zh_CN: add damon faq translation

Translate .../vm/damon/faq.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Alex Shi <alexs@kernel.org>
Link: https://lore.kernel.org/r/30507f807a835360f57bb9498c37f4c3644b33b7.1642230669.git.siyanteng@loongson.cn


Signed-off-by: Jonathan Corbet <corbet@lwn.net>