[easytag] Fix compilation if MP3 support is disabled

[David King <davidk src gnome org>]

commit 61fc11a2d7b6c1a833f40f644b70be2f46ad90bb
Author: David King <amigadave amigadave com>
Date:   Fri Mar 27 14:38:27 2015 +0100

    Fix compilation if MP3 support is disabled

 src/application_window.c |    2 +-
 src/file_list.c          |    2 +-
 src/preferences_dialog.c |    2 ++
 src/tag_area.c           |    3 ---
 4 files changed, 4 insertions(+), 5 deletions(-)
---
diff --git a/src/application_window.c b/src/application_window.c
index 6813512..52977b4 100644
--- a/src/application_window.c
+++ b/src/application_window.c
@@ -2332,7 +2332,7 @@ et_application_window_display_et_file (EtApplicationWindow *self,
             break;
 #endif
         case OFR_FILE:
-#if !defined ENABLE_MP3 && defined ENABLE_ID3LIB
+#if !defined ENABLE_MP3 && !defined ENABLE_ID3LIB
         case MP3_FILE:
         case MP2_FILE:
 #endif
diff --git a/src/file_list.c b/src/file_list.c
index 40da814..6695231 100644
--- a/src/file_list.c
+++ b/src/file_list.c
@@ -404,7 +404,7 @@ et_file_list_add (GList *file_list,
             break;
 #endif
         case OFR_FILE:
-#if !defined ENABLE_MP3 && defined ENABLE_ID3LIB
+#if !defined ENABLE_MP3 && !defined ENABLE_ID3LIB
         case MP3_FILE:
         case MP2_FILE:
 #endif
diff --git a/src/preferences_dialog.c b/src/preferences_dialog.c
index f2e9e8a..92a9a18 100644
--- a/src/preferences_dialog.c
+++ b/src/preferences_dialog.c
@@ -125,6 +125,7 @@ on_default_path_changed (GSettings *settings,
     g_variant_unref (default_path);
 }
 
+#ifdef ENABLE_ID3LIB
 static gboolean
 et_preferences_id3v2_version_get (GValue *value,
                                   GVariant *variant,
@@ -153,6 +154,7 @@ et_preferences_id3v2_version_set (const GValue *value,
 
     return id3v24;
 }
+#endif /* ENABLE_ID3LIB */
 
 static gboolean
 et_preferences_id3v2_unicode_charset_get (GValue *value,
diff --git a/src/tag_area.c b/src/tag_area.c
index 4c37181..81cbb63 100644
--- a/src/tag_area.c
+++ b/src/tag_area.c
@@ -2651,9 +2651,6 @@ et_tag_area_update_controls (EtTagArea *self,
             break;
 #endif /* ENABLE_WAVPACK */
 
-#ifndef ENABLE_MP3
-        case ID3_TAG:
-#endif
 #ifndef ENABLE_OGG
         case OGG_TAG:
 #endif