CONFIG_ARCH_MX5 is not available for the default architecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_ARCH_MX5.
Result is shown for kernelversion 5.6.17

i.MX50, i.MX51, i.MX53

configname: CONFIG_ARCH_MX5

Freescale CPU family:
└─> i.MX50, i.MX51, i.MX53

This enables support for machines using Freescale's i.MX50 and i.MX53