ZJIT: Revert self_val removal and rename it to recv (ruby#14504)

* Revert "ZJIT: Removed unused self_val from Send"

This reverts commit 13c2f8d.

* Revert "ZJIT: Removed unused self_val from InvokeSuper"

This reverts commit 877b625.

* ZJIT: Rename self_val in dispatching HIRs to recv

* ZJIT: Remove unnecessary constructor param names

Author: st0012

zjit/src/codegen.rs

@@ -367,7 +367,7 @@ fn gen_insn(cb: &mut CodeBlock, jit: &mut JITState, asm: &mut Assembler, functio
         // Give up SendWithoutBlockDirect for 6+ args since asm.ccall() doesn't support it.
         Insn::SendWithoutBlockDirect { cd, state, args, .. } if args.len() + 1 > C_ARG_OPNDS.len() => // +1 for self
             gen_send_without_block(jit, asm, *cd, &function.frame_state(*state)),
-        Insn::SendWithoutBlockDirect { cme, iseq, self_val, args, state, .. } => gen_send_without_block_direct(cb, jit, asm, *cme, *iseq, opnd!(self_val), opnds!(args), &function.frame_state(*state)),
+        Insn::SendWithoutBlockDirect { cme, iseq, recv, args, state, .. } => gen_send_without_block_direct(cb, jit, asm, *cme, *iseq, opnd!(recv), opnds!(args), &function.frame_state(*state)),
         &Insn::InvokeSuper { cd, blockiseq, state, .. } => gen_invokesuper(jit, asm, cd, blockiseq, &function.frame_state(state)),
         Insn::InvokeBlock { cd, state, .. } => gen_invoke_block(jit, asm, *cd, &function.frame_state(*state)),
         // Ensure we have enough room fit ec, self, and arguments