CONFIG_RAMAUTOBIT is not available for thedefaultarchitecture x86.
Result is shown for architecture m68k
default or selected kernelversion does not have config value CONFIG_RAMAUTOBIT.
Result is shown for kernelversion 6.2.5

AUTO

configname: CONFIG_RAMAUTOBIT

RAM bus width
└─>AUTO
In linux kernel since version 2.6.12  
Select the physical RAM data bus size. Not needed on most platforms,
so you can generally choose AUTO.