remove unused variable (#3920)

Signed-off-by: Jens Mueller <tschenser@gmx.de>

src/main/java/com/owncloud/android/datamodel/OCFile.java

@@ -69,7 +69,6 @@ public class OCFile implements Parcelable, Comparable<OCFile>, ServerFileInterfa
     @Getter private boolean needsUpdatingWhileSaving;
     @Getter @Setter private long lastSyncDateForProperties;
     @Getter @Setter private long lastSyncDateForData;
-    @Getter @Setter private boolean availableOffline;
     @Getter @Setter private boolean previewAvailable;
     @Getter private String etag;
     @Getter private String etagOnServer;