CONFIG_ARM64_ERRATUM_2658417 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm64

Cortex-A510: 2658417: remove BF16 support due to incorrect result

configname: CONFIG_ARM64_ERRATUM_2658417

Linux Kernel Configuration
└─>Kernel Features
└─>ARM errata workarounds via the alternatives framework
└─>Cortex-A510: 2658417: remove BF16 support due to incorrect result
In linux kernel since version 6.1 (release Date: 2022-12-11)  
This option adds the workaround for ARM Cortex-A510 erratum 2658417.
Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
BFMMLA or VMMLA instructions in rare circumstances when a pair of
A510 CPUs are using shared neon hardware. As the sharing is not
discoverable by the kernel, hide the BF16 HWCAP to indicate that
user-space should not be using these instructions.

If unsure, say Y.