CONFIG_DEBUG_AM33XXUART1 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Kernel low-level debugging messages via AM33XX UART1

configname: CONFIG_DEBUG_AM33XXUART1

Kernel low-level debugging port
└─>Kernel low-level debugging messages via AM33XX UART1
In linux kernel since version 3.1 (release Date: 2011-10-24)