default or selected kernelversion does not have config value CONFIG_BLK_DEV_CMD64X.
Result is shown for kernelversion 6.9.9

CMD64{3|6|8|9} chipset support

modulename: cmd64x.ko

configname: CONFIG_BLK_DEV_CMD64X

Linux Kernel Configuration
└─>Device Drivers
└─>ATA/ATAPI/MFM/RLL support (DEPRECATED)
└─>CMD64{3|6|8|9} chipset support
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Say Y here if you have an IDE controller which uses any of these
chipsets: CMD643, CMD646, or CMD648.

source code:
drivers/ide/cmd64x.c