No, xml files are not automatically generated.
They are stored as examples in the reference design provided in the example folder during SoC EDS installation.
(Example:
C:\intelFPGA\18.1\embedded\examples\hardware\cv_soc_devkit_ghrd\hps_common_board_info.xml
C:\intelFPGA\18.1\embedded\examples\ hardware\cv_soc_devkit_ghrd\soc_system_board_info.xml