nv50/ir: use override

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23656>

src/nouveau/codegen/nv50_ir_lowering_gm107.h

@@ -7,9 +7,9 @@ class GM107LoweringPass : public NVC0LoweringPass
 public:
    GM107LoweringPass(Program *p) : NVC0LoweringPass(p) {}
 private:
-   virtual bool visit(Instruction *);
+   bool visit(Instruction *) override;
 
-   virtual bool handleManualTXD(TexInstruction *);
+   bool handleManualTXD(TexInstruction *) override;
    bool handleDFDX(Instruction *);
    bool handlePFETCH(Instruction *);
    bool handlePOPCNT(Instruction *);
@@ -19,7 +19,7 @@ private:
 class GM107LegalizeSSA : public NVC0LegalizeSSA
 {
 private:
-   virtual bool visit(Instruction *);
+   bool visit(Instruction *) override;
 
 protected:
    void handlePFETCH(Instruction *);

src/nouveau/codegen/nv50_ir_lowering_nvc0.h

@@ -57,8 +57,8 @@ namespace nv50_ir {
 class NVC0LegalizeSSA : public Pass
 {
 private:
-   virtual bool visit(BasicBlock *);
-   virtual bool visit(Function *);
+   bool visit(BasicBlock *) override;
+   bool visit(Function *) override;
 
    // we want to insert calls to the builtin library only after optimization
    void handleDIV(Instruction *); // integer division, modulus
@@ -81,8 +81,8 @@ public:
    NVC0LegalizePostRA(const Program *);
 
 private:
-   virtual bool visit(Function *);
-   virtual bool visit(BasicBlock *);
+   bool visit(Function *) override;
+   bool visit(BasicBlock *) override;
 
    void replaceCvt(Instruction *);
    void replaceZero(Instruction *);
@@ -155,11 +155,11 @@ protected:
    void checkPredicate(Instruction *);
    Value *loadMsAdjInfo32(TexInstruction::Target targ, uint32_t index, int slot, Value *ind, bool bindless);
 
-   virtual bool visit(Instruction *);
+   bool visit(Instruction *) override;
 
 private:
-   virtual bool visit(Function *);
-   virtual bool visit(BasicBlock *);
+   bool visit(Function *) override;
+   bool visit(BasicBlock *) override;
 
    void readTessCoord(LValue *dst, int c);