CONFIG_DDB5476 is not available for thedefaultarchitecture x86.
Result is shown for architecture mips
default or selected kernelversion does not have config value CONFIG_DDB5476.
Result is shown for kernelversion 5.4.123

Support for NEC DDB Vrc-5476

modulename: ops-ddb5476.ko

configname: CONFIG_DDB5476

Linux/MIPS Kernel Configuration
└─>Machine selection
└─>Support for NEC DDB Vrc-5476
In linux kernel since version 2.6.12  
This enables support for the R5432-based NEC DDB Vrc-5476
evaluation board.

Features : kernel debugging, serial terminal, NFS root fs, on-board
ether port USB, AC97, PCI, PCI VGA card & framebuffer console,
IDE controller, PS2 keyboard, PS2 mouse, etc.

source code: