Fix headers for USE="lyrics -cover -taglib"
Add missing dependency, include guard
https://bugs.gentoo.org/919181
--- a/src/gimmix-lyrics.h
+++ b/src/gimmix-lyrics.h
@@ -4,6 +4,7 @@
 #define GIMMIX_LYRICS_H
 
 #include "gimmix-core.h"
+#include "gimmix-metadata.h"
 #include "gimmix.h"
 #include "wejpconfig.h"
 #include <gtk/gtk.h>
--- a/src/gimmix-metadata.h
+++ b/src/gimmix-metadata.h
@@ -1,5 +1,5 @@
 #ifndef GIMMIX_METADATA_H
-#define GIMMIX_METADAT_H
+#define GIMMIX_METADATA_H
 
 #include "gimmix-core.h"
 #include "gimmix.h"