update the deepks interface documentation (#1309)

* modified doc advanced.md

* added documentation for SCF complex environment part

* update the deepks interface documentation

Co-authored-by: hongriTianqi <hongriTianqi@users.noreply.github.com>
Co-authored-by: Wenfei Li <38569667+wenfei-li@users.noreply.github.com>

docs/advanced/interface/deepks.md

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 # DeePKS
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+[DeePKS](https://pubs.acs.org/doi/10.1021/acs.jctc.0c00872) is a machine-learning aided density funcitonal model that fits the energy difference between highly accurate but computationally demanding method and effcient but less accurate method via neural-network. As such, the trained DeePKS model can provide highly accurate energetics (and forces) with relatively low computational cost, and can therefore act as a bridge to connect expensive quantum mechanic data and machine-learning-based potentials. While the original framework of DeePKS is for molecular systems, please refer to this [reference]((https://arxiv.org/abs/2206.10093)) for the application of DeePKS in periodic systems. 
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+Detailed instructions on installing and running DeePKS can be found on this [website](https://deepks-kit.readthedocs.io/en/latest/index.html). An [example](https://github.com/deepmodeling/deepks-kit/tree/abacus/examples/water_single_lda2pbe_abacus) for training DeePKS model with ABACUS is also provided. The DeePKS-related keywords in `INPUT` file can be found [here](https://github.com/deepmodeling/abacus-develop/blob/develop/docs/input-main.md#deepks).
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+> Note: Use the LCAO basis for DeePKS-related calculations
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+