[ModuleUtils][KCFI] Set !kcfi_type metadata for sanitizer constructors

Set KCFI type metadata for the sanitizer constructors to prevent
runtime failures when these functions are indirectly called in
instrumented code. This fixes a compatibility issue with KASAN and
-fsanitize=kcfi in the Linux kernel.

Link: https://github.com/ClangBuiltLinux/linux/issues/1742

Reviewed By: nickdesaulniers, MaskRay

Differential Revision: https://reviews.llvm.org/D138945