docs/zh_CN: core-api: Add idr Chinese translation

docs/zh_CN: core-api: Add idr Chinese translation

Translate core-api/idr.rst into Chinese.

Last English version used:

commit 85656ec193e9 ("IDR: Note that the IDR API is deprecated").

Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Reviewed-by: Yanteng Si<siyanteng@loongson.cn>
Reviewed-by: Alex Shi <alexs@kernel.org>
Link: https://lore.kernel.org/r/9f578ea087df7ef8665fc08541d208e7429176ec.1660881950.git.zhoubinbin@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>