clang-tidy: use default

Signed-off-by: Rosen Penev <rosenp@gmail.com>

include/exiv2/error.hpp

@@ -262,7 +262,7 @@ class EXIV2API Error : public std::exception {
   }
 
   //! Virtual destructor. (Needed because of throw())
-  ~Error() noexcept override;
+  ~Error() noexcept override = default;
   //@}
 
   //! @name Accessors

src/error.cpp

@@ -153,9 +153,6 @@ Error::Error(ErrorCode code) : code_(code) {
   setMsg(0);
 }
 
-Error::~Error() noexcept {
-}
-
 ErrorCode Error::code() const noexcept {
   return code_;
 }