`ks_solver` can be `dav_subspace` for PW GPU

[MoseyQAQ]

Details

In the documentation related to CUDA GPU acceleration, it's stated that for PW GPU, the ks_solver could be cg, bpcg or dav; The dav_subspace is reported here.

abacus-develop/docs/advanced/acceleration/cuda.md

Line 47 in 74c4269

- Set `ks_solver`: For the PW basis, CG, BPCG and Davidson methods are supported on GPU; set the input parameter [ks_solver](../input_files/input-main.md#ks_solver) to `cg`, `bpcg` or `dav`. For the LCAO basis, `cusolver`, `cusolvermp` and `elpa` is supported on GPU.

However, now the ks_solver dav_subspace supports CUDA GPU acceleration. A clear example is that abacus has corresponding test for this tests/11_PW_GPU/scf_dav_sub.

I think it would be great if abacus can add a clear note that dav_subspace also supports GPU

Have you read the online manual http://abacus.deepmodeling.com/en/latest/

• Yes, I have read the online manual.

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