lib/model: Remove unused func (#6456)

lib/model/model.go

@@ -2562,30 +2562,6 @@ func (m *model) checkFolderRunningLocked(folder string) error {
 	return errFolderNotRunning
 }
 
-// checkFolderDeviceStatusLocked first checks the folder and then whether the
-// given device is connected and shares this folder.
-// Need to hold (read) lock on both m.fmut and m.pmut when calling this.
-func (m *model) checkDeviceFolderConnectedLocked(device protocol.DeviceID, folder string) error {
-	if err := m.checkFolderRunningLocked(folder); err != nil {
-		return err
-	}
-
-	if cfg, ok := m.cfg.Device(device); !ok {
-		return errDeviceUnknown
-	} else if cfg.Paused {
-		return errDevicePaused
-	}
-
-	if _, ok := m.conn[device]; !ok {
-		return errors.New("device is not connected")
-	}
-
-	if cfg, ok := m.cfg.Folder(folder); !ok || !cfg.SharedWith(device) {
-		return errors.New("folder is not shared with device")
-	}
-	return nil
-}
-
 // mapFolders returns a map of folder ID to folder configuration for the given
 // slice of folder configurations.
 func mapFolders(folders []config.FolderConfiguration) map[string]config.FolderConfiguration {