qt: Add media history manager for recently used images

src/include/86box/cdrom.h

@@ -39,6 +39,8 @@
 #define CD_TOC_SESSION			1
 #define CD_TOC_RAW			2
 
+#define CD_IMAGE_HISTORY                4
+
 #define BUF_SIZE 32768
 
 #define CDROM_IMAGE 200
@@ -110,6 +112,8 @@ typedef struct cdrom {
     char image_path[1024],
          prev_image_path[1024];
 
+    char *image_history[CD_IMAGE_HISTORY];
+
     uint32_t sound_on, cdrom_capacity,
              pad, seek_pos,
              seek_diff, cd_end;