Begin work on support objc intrinsics

src/llvm_backend_proc.cpp

@@ -2106,6 +2106,9 @@ lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValue const &tv,
 			res.type = t_uintptr;
 			return res;
 		}
+
+	case BuiltinProc_objc_send:
+		return lb_handle_obj_send(p, expr);
 	}
 
 	GB_PANIC("Unhandled built-in procedure %.*s", LIT(builtin_procs[id].name));