AVIF: added support to XMP and EXIF metadata

Allow to load/save info about:
- GPS info (latitude, longitude, altitude)
- Various text info (title, description, author, copyright, etc...)
- Image resolution

The compatibility of the modifications has been tested with GIMP.

src/imageformats/microexif_p.h

@@ -269,6 +269,14 @@ public:
      */
     static MicroExif fromByteArray(const QByteArray &ba);
 
+    /*!
+     * \brief fromRawData
+     * Creates the class from RAW EXIF data.
+     * \return The created class (empty on error).
+     * \sa isEmpty
+     */
+    static MicroExif fromRawData(const char *data, size_t size);
+
     /*!
      * \brief fromDevice
      * Creates the class from a device.