CONFIG_DEBUG_MSTARV7_PMUART is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Kernel low-level debugging messages via MSTARV7 PM UART

configname: CONFIG_DEBUG_MSTARV7_PMUART

Kernel low-level debugging port
└─>Kernel low-level debugging messages via MSTARV7 PM UART
In linux kernel since version 5.2 (release Date: 2019-07-07)  
Say Y here if you want kernel low-level debugging support
for MSTAR ARMv7-based platforms on PM UART.