[CodeGen] Disable default copy ctor and copy assignment operator for class Scoreboard

[pengfei]

LGTM.

llvm/include/llvm/CodeGen/ScoreboardHazardRecognizer.h

class Scoreboard {
     // that all hazards can be tracked.
     size_t Depth = 0;
 
     // Indices into the Scoreboard that represent the current cycle.
     size_t Head = 0;
 
   public:
     Scoreboard() = default;
-
+    Scoreboard &operator=(const Scoreboard &other) = delete;
+    Scoreboard(const Scoreboard &other) = delete;
     ~Scoreboard() {
       delete[] Data;
     }
 
     size_t getDepth() const { return Depth; }
 
     InstrStage::FuncUnits& operator[](size_t idx) const {
       // Depth is expected to be a power-of-2.