[memprof] Remove redundant virtual (NFC) (#94858)

'override' makes 'virtual' redundant.

Identified with modernize-use-override.

Author: kazutakahirata

llvm/include/llvm/ProfileData/MemProfReader.h

@@ -137,7 +137,7 @@ class RawMemProfReader final : public MemProfReader {
 public:
   RawMemProfReader(const RawMemProfReader &) = delete;
   RawMemProfReader &operator=(const RawMemProfReader &) = delete;
-  virtual ~RawMemProfReader() override = default;
+  ~RawMemProfReader() override = default;
 
   // Prints the contents of the profile in YAML format.
   void printYAML(raw_ostream &OS);
@@ -161,7 +161,7 @@ class RawMemProfReader final : public MemProfReader {
   // Returns a list of build ids recorded in the segment information.
   static std::vector<std::string> peekBuildIds(MemoryBuffer *DataBuffer);
 
-  virtual Error
+  Error
   readNextRecord(GuidMemProfRecordPair &GuidRecord,
                  std::function<const Frame(const FrameId)> Callback) override;