AArch64: implement IFUNC

[marxin]

That's something that needs to emit a PLT GOT entry that is called:

wild/libwild/src/x86_64.rs

Lines 118 to 129 in 864c956

	// IFuncs cannot be referenced directly. The always need to go via the GOT. So if we've got
	// say a PLT32 relocation, we don't want to relax it even if we're in a static executable.
	// Furthermore, if we encounter a relocation like PC32 to an ifunc, then we need to change
	// it so that it goes via the GOT. This is kind of the opposite of relaxation.
	if value_flags.contains(ValueFlags::IFUNC) {
	return match relocation_kind {
	object::elf::R_X86_64_PC32 => {
	return create(RelaxationKind::NoOp, object::elf::R_X86_64_PLT32);
	}
	_ => None,
	};
	}