CONFIG_NR_DMA_CHANNELS_BOOL is not available for thedefaultarchitecture x86.
Result is shown for architecture sh
default or selected kernelversion does not have config value CONFIG_NR_DMA_CHANNELS_BOOL.
Result is shown for kernelversion 6.2.5

Override default number of maximum DMA channels


Linux Kernel Configuration
└─>DMA support
└─>Override default number of maximum DMA channels
In linux kernel since version 2.6.12  
This allows you to forcibly update the maximum number of supported
DMA channels for a given board. If this is unset, this will default
to the number of channels that the on-chip DMAC has.