julec: remove legacy built-in function handling

Author: mertcandav

src/julec/obj/cxx/ident.jule

@@ -96,13 +96,6 @@ impl identCoder {
 	}
 
 	fn funcIns(mut &buf: *strings::Builder, mut f: &sema::FuncIns) {
-		if f.IsBuiltin() {
-			// Do not use [identCoder.writeIdentTo] for this.
-			// Built-in functions are always ASCII.
-			buf.WriteStr("jule::")!
-			buf.WriteStr(f.Decl.Name)!
-			ret
-		}
 		if f.Decl.Extern || len(f.Generics) == 0 {
 			identCoder.func(buf, f.Decl)
 			ret