CONFIG_ARCH_VEXPRESS_CORTEX_A5_A9_ERRATA is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Enable A5 and A9 only errata work-arounds

configname: CONFIG_ARCH_VEXPRESS_CORTEX_A5_A9_ERRATA

Linux Kernel Configuration
└─>ARM Ltd. Versatile Express family
└─>Enable A5 and A9 only errata work-arounds
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Provides common dependencies for Versatile Express platforms
based on Cortex-A5 and Cortex-A9 processors. In order to
build a working kernel, you must also enable relevant core
tile support or Flattened Device Tree based support options.