CONFIG_CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS is not available for thedefaultarchitecture x86.
Result is shown for architecture arm64

CONFIG_CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS (not configurable)

configname: CONFIG_CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS

Linux Kernel Configuration
└─>CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS
In linux kernel since version 5.2 (release Date: 2019-07-07)  

depends
CONFIG_AS_IS_GNU or CONFIG_AS_IS_LLVM
CONFIG_LD_IS_LLD or CONFIG_LD_VERSIONCONFIG_23600