[Refactor] Remove Unused Member Variables in AtomicAddNode and CopyNode

- Removed the `args_` member variable from both `AtomicAddNode` and `CopyNode` classes to streamline the code and eliminate unnecessary data members.
- This change enhances code clarity and maintainability by focusing on relevant attributes for each class.

Author: LeiWang1999

src/op/atomic_add.h

@@ -17,8 +17,6 @@ using namespace tir;
 
 class AtomicAddNode : public TileOperatorNode {
 public:
-  Array<PrimExpr> args_;
-
   Buffer src, dst;
   Array<Range> src_range, dst_range;
   IntImm coalesced_width;

src/op/copy.h

@@ -96,8 +96,6 @@ struct TMAIm2ColDesc {
  */
 class CopyNode : public TileOperatorNode {
 public:
-  Array<PrimExpr> args_; // Copy parameters (indices, sizes, etc.)
-
   Buffer src, dst;                   // Source and destination buffers
   Array<Range> src_range, dst_range; // Ranges for each dimension in src and dst
   IntImm coalesced_width; // Width (in elements) for coalesced memory access