Build KUnit tests for ELF binary support

configname: CONFIG_BINFMT_ELF_KUNIT_TEST

Linux Kernel Configuration
└─>Executable file formats
└─>Build KUnit tests for ELF binary support
In linux kernel since version 5.2 (release Date: 2019-07-07)  
This builds the ELF loader KUnit tests, which try to gather
prior bug fixes into a regression test collection. This is really
only needed for debugging. Note that with CONFIG_COMPAT=y, the
compat_binfmt_elf KUnit test is also created.