properly mark functions as deprecated

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

include/exiv2/image.hpp

@@ -430,9 +430,9 @@ class EXIV2API Image {
   [[nodiscard]] AccessMode checkMode(MetadataId metadataId) const;
   /*!
     @brief Check if image supports a particular type of metadata.
-       This method is deprecated. Use checkMode() instead.
+    @deprecated This method is deprecated. Use checkMode() instead.
    */
-  [[nodiscard]] bool supportsMetadata(MetadataId metadataId) const;
+  [[deprecated]] [[nodiscard]] bool supportsMetadata(MetadataId metadataId) const;
   //! Return the flag indicating the source when writing XMP metadata.
   [[nodiscard]] bool writeXmpFromPacket() const;
   //! Return list of native previews. This is meant to be used only by the PreviewManager.

include/exiv2/iptc.hpp

@@ -96,10 +96,11 @@ class EXIV2API Iptcdatum : public Metadatum {
    */
   [[nodiscard]] std::string key() const override;
   /*!
-     @brief Return the name of the record (deprecated)
+     @brief Return the name of the record
      @return record name
+     @deprecated This function is deprecated.
    */
-  [[nodiscard]] std::string recordName() const;
+  [[deprecated]] [[nodiscard]] std::string recordName() const;
   /*!
      @brief Return the record id
      @return record id