YJIT: Use general definedivar at the end of chains (#7756)

Merged-By: k0kubun <takashikkbn@gmail.com>

yjit/src/codegen.rs

@@ -2417,7 +2417,7 @@ fn gen_definedivar(
     // Specialize base on compile time values
     let comptime_receiver = jit.peek_at_self();
 
-    if comptime_receiver.shape_too_complex() {
+    if comptime_receiver.shape_too_complex() || asm.ctx.get_chain_depth() as i32 >= GET_IVAR_MAX_DEPTH {
         // Fall back to calling rb_ivar_defined
 
         // Save the PC and SP because the callee may allocate