default or selected kernelversion does not have config value CONFIG_X86_DMA_REMAP.
Result is shown for kernelversion 6.9.9

CONFIG_X86_DMA_REMAP (not configurable)

configname: CONFIG_X86_DMA_REMAP

Linux Kernel Configuration
└─>X86_DMA_REMAP
In linux kernel since version 3.1 (release Date: 2011-10-24)  
depends
CONFIG_STA2X11