Merge git://git.infradead.org/ubifs-2.6

* git://git.infradead.org/ubifs-2.6:
  UBIFS: fix return code in check_leaf
  UBI: flush wl before clearing update marker
  MAINTAINERS: change e-mail of Artem Bityutskiy
  UBIFS: remove manual O_SYNC handling
  UBIFS: support mounting of UBI volume character devices
  UBI: Add ubi_open_volume_path