default or selected kernelversion does not have config value CONFIG_BLK_DEV_IT821X.
Result is shown for kernelversion 6.9.9

IT821X IDE support

modulename: it821x.ko

configname: CONFIG_BLK_DEV_IT821X

Linux Kernel Configuration
└─>Device Drivers
└─>ATA/ATAPI/MFM/RLL support (DEPRECATED)
└─>IT821X IDE support
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
This driver adds support for the ITE 8211 IDE controller and the
IT 8212 IDE RAID controller in both RAID and pass-through mode.

source code: