CONFIG_DEBUG_SOCFPGA_UART1 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_DEBUG_SOCFPGA_UART1.
Result is shown for kernelversion 6.5.1

Use SOCFPGA UART1 for low-level debug

configname: CONFIG_DEBUG_SOCFPGA_UART1

Kernel low-level debugging port
└─>Use SOCFPGA UART1 for low-level debug
In linux kernel since version 4.1 (release Date: 2015-06-21)  
Say Y here if you want kernel low-level debugging support
on SOCFPGA(Arria 10) based platforms.