CONFIG_DEBUG_HIX5HD2_UART is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Hisilicon Hix5hd2 Debug UART

configname: CONFIG_DEBUG_HIX5HD2_UART

Kernel low-level debugging port
└─>Hisilicon Hix5hd2 Debug UART
In linux kernel since version 3.17 (release Date: 2014-10-05)  
Say Y here if you want kernel low-level debugging support
on Hix5hd2 UART.