Update input-main.md (#1167)

* Update input-main.md

Delete the link for the deepks branch, which is not available anymore.

* Update docs/input-main.md

Co-authored-by: Chun Cai <amoycaic@gmail.com>

Co-authored-by: Chun Cai <amoycaic@gmail.com>

Author: ouqi0711

docs/input-main.md

@@ -942,7 +942,7 @@ This part of variables are used to control the calculation of DOS.
 ### DeePKS
 
 This part of variables are used to control the usage of DeePKS method (a comprehensive data-driven approach to improve accuracy of DFT).
-Warning: this function is not robust enough for version 2.2.0. Please try these variables in <https://github.com/deepmodeling/abacus-develop/tree/deepks> .
+Warning: this function is not robust enough for the current version. Please try the following variables at your own risk:
 
 #### deepks_out_labels
 
@@ -1642,4 +1642,4 @@ Thermal conductivities: $\kappa = \lim_{\omega\to 0}\kappa(\omega)$
 
 - **Type**: Integer
 - **Description**: We use gaussian functions to approxiamte $\delta(E)\approx \frac{1}{\sqrt{2\pi}\Delta E}e^{-\frac{E^2}{2{\Delta E}^2}}$. FWHM for conductivities, $FWHM=2*\sqrt{2\ln2}\cdot \Delta E$. The unit is eV.
-- **Default**: 0.3
+- **Default**: 0.3