CONFIG_DUMPTOFLASH is not available for thedefaultarchitecture x86.
Result is shown for architecture m68knommu
default or selected kernelversion does not have config value CONFIG_DUMPTOFLASH.
Result is shown for kernelversion 5.4.123

Panic/Dump to FLASH

configname: CONFIG_DUMPTOFLASH

Linux Kernel Configuration
└─>Kernel hacking
└─>Panic/Dump to FLASH
In linux kernel since version 2.6.12  
Dump any panic of trap output into a flash memory segment
for later analysis.

depends
CONFIG_COLDFIRE