BitField: Add an explicit evaluation method.

Sometimes it can be beneficial to use this in places where an explicit cast needs to happen otherwise. By using the evaluation method, it's not necessary anymore to explicitly write the underlying type in this case.

src/common/bit_field.h

@@ -131,6 +131,11 @@ public:
     }
 
     __forceinline operator T() const
+    {
+        return Value();
+    }
+
+    __forceinline T Value() const
     {
         if (std::numeric_limits<T>::is_signed)
         {