CONFIG_ARC_BUILTIN_DTB_NAME is not available for thedefaultarchitecture x86.
Result is shown for architecture arc
default or selected kernelversion does not have config value CONFIG_ARC_BUILTIN_DTB_NAME.
Result is shown for kernelversion 6.9.9

Built in DTB

configname: CONFIG_ARC_BUILTIN_DTB_NAME

Linux Kernel Configuration
└─>ARC Architecture Configuration
└─>Built in DTB
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Set the name of the DTB to embed in the vmlinux binary
Leaving it blank selects the minimal "skeleton" dtb