CONFIG_ARM64_ERRATUM_843419 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm64

Cortex-A53: 843419: A load or store might access an incorrect address

configname: CONFIG_ARM64_ERRATUM_843419

Linux Kernel Configuration
└─>Kernel Features
└─>ARM errata workarounds via the alternatives framework
└─>Cortex-A53: 843419: A load or store might access an incorrect address
In linux kernel since version 3.10 (release Date: 2013-06-30)  
This option links the kernel with '--fix-cortex-a53-843419' and
builds modules using the large memory model in order to avoid the use
of the ADRP instruction, which can cause a subsequent memory access
to use an incorrect address on Cortex-A53 parts up to r0p4.

If unsure, say Y.