CONFIG_XTENSA_SIMCALL_ISS is not available for thedefaultarchitecture x86.
Result is shown for architecture xtensa

simcall

configname: CONFIG_XTENSA_SIMCALL_ISS

Semihosting interface
└─>simcall
In linux kernel since version 5.2 (release Date: 2019-07-07)  
Use simcall instruction. simcall is only available on simulators,
it does nothing on hardware.