CONFIG_DEBUG_SIRFATLAS7_UART1 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Kernel low-level debugging messages via SiRFatlas7 UART1

configname: CONFIG_DEBUG_SIRFATLAS7_UART1

Kernel low-level debugging port
└─>Kernel low-level debugging messages via SiRFatlas7 UART1
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 uart1 port on SiRFATLAS7 devices.