macosx: Do not display "all favorites" section within favorites library if there is only one favorites type present

Signed-off-by: Claudio Cambra <developer@claudiocambra.com>

modules/gui/macosx/library/favorites-library/VLCLibraryFavoritesDataSource.m

@@ -163,14 +163,16 @@ NSString * const VLCLibraryFavoritesDataSourceDisplayedCollectionChangedNotifica
 - (void)updateVisibleSectionMapping
 {
     NSMutableArray<NSNumber *> * const visibleSections = [NSMutableArray array];
-    
-    for (NSUInteger i = 0; i < VLCLibraryFavoritesSectionCount; i++) {
+    for (NSUInteger i = 1; i < VLCLibraryFavoritesSectionCount; i++) {
         NSArray * const sectionArray = [self arrayForSection:i];
         if (sectionArray.count > 0) {
             [visibleSections addObject:@(i)];
         }
     }
-    
+    if (visibleSections.count > 1) {
+        [visibleSections insertObject:@(VLCLibraryFavoritesSectionAllFavorites) atIndex:0];
+    }
+
     _visibleSectionMapping = [visibleSections copy];
 }