CONFIG_DEBUG_UART_8250_WORD is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Use 32-bit accesses for 8250 UART

configname: CONFIG_DEBUG_UART_8250_WORD

Linux Kernel Configuration
└─>Use 32-bit accesses for 8250 UART
In linux kernel since version 3.12 (release Date: 2013-11-03)  
depends
CONFIG_DEBUG_UART_8250_SHIFT=2
CONFIG_DEBUG_LL_UART_8250 or CONFIG_DEBUG_UART_8250