CONFIG_DEBUG_DIGICOLOR_UA0 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Kernel low-level debugging messages via Digicolor UA0

configname: CONFIG_DEBUG_DIGICOLOR_UA0

Kernel low-level debugging port
└─>Kernel low-level debugging messages via Digicolor UA0
In linux kernel since version 4 (release Date: 2015-04-12)  
Say Y here if you want the debug print routines to direct
their output to the UA0 serial port in the CX92755.