Tweak UTDecoder

• add [[nodiscard]]
• add constexpr
• remove redundant data members
• fix clang warning about class vs. struct on Microsoft platforms...

UT/UTDAQ/UTDAQ/UTADCWord.h

@@ -28,27 +28,29 @@ public:
   /** constructer with int
     @param value
     */
-  explicit UTADCWord( unsigned int value ) : m_value( value ) {}
+  explicit constexpr UTADCWord( unsigned int value ) : m_value( value ) {}
 
-  UTADCWord( unsigned int value, unsigned int nlane ) : m_value( value ), m_lane( nlane ){};
+  constexpr UTADCWord( unsigned int value, unsigned int nlane ) : m_value( value ), m_lane( nlane ){};
 
   /** The actual value
     @return value
     */
-  unsigned int value() const { return m_value; };
+  [[nodiscard]] constexpr unsigned int value() const { return m_value; };
 
-  unsigned int channelID() const {
+  [[nodiscard]] constexpr unsigned int channelID() const {
     return ( ( m_value & static_cast<int>( mask::strip ) ) >> static_cast<int>( bits::strip ) ) +
            static_cast<int>( bits::maxstrip ) * m_lane;
   }
 
-  unsigned int adc() const { return ( m_value & static_cast<int>( mask::adc ) ) >> static_cast<int>( bits::adc ); }
+  [[nodiscard]] constexpr unsigned int adc() const {
+    return ( m_value & static_cast<int>( mask::adc ) ) >> static_cast<int>( bits::adc );
+  }
 
-  unsigned int fracStripBits() const { return 0; }
+  [[nodiscard]] constexpr unsigned int fracStripBits() const { return 0; }
 
-  unsigned int pseudoSizeBits() const { return 0; }
+  [[nodiscard]] constexpr unsigned int pseudoSizeBits() const { return 0; }
 
-  bool hasHighThreshold() const { return true; }
+  [[nodiscard]] constexpr bool hasHighThreshold() const { return true; }
 
   /** Operator overloading for stringoutput */
   friend std::ostream& operator<<( std::ostream& s, const UTADCWord& obj ) { return obj.fillStream( s ); }