CONFIG_KERNEL_ABI_CALL0 is not available for thedefaultarchitecture x86.
Result is shown for architecture xtensa

Call0 ABI


Kernel ABI
└─>Call0 ABI
In linux kernel since version 5.2 (release Date: 2019-07-07)  
Select this option to compile kernel code with call0 ABI even with
toolchain that defaults to windowed ABI.
When this option is not selected the default toolchain ABI will
be used for the kernel code.