CONFIG_DEBUG_STIH41X_SBC_ASC1 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Use StiH415/416 SBC ASC1 UART for low-level debug

configname: CONFIG_DEBUG_STIH41X_SBC_ASC1

Kernel low-level debugging port
└─>Use StiH415/416 SBC ASC1 UART for low-level debug
In linux kernel since version 5.2 (release Date: 2019-07-07)  
Say Y here if you want kernel low-level debugging support
on STiH415/416 based platforms like b2020. which has
default UART wired up to SBC ASC1.

If unsure, say N.

depends
CONFIG_ARCH_STI