ANDROID: sdcardfs: support direct-IO (DIO) operations

This comes from the wrapfs patch
2e346c83b26e Wrapfs: support direct-IO (DIO) operations

Signed-off-by: Li Mengyang <li.mengyang@stonybrook.edu>
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Bug: 34133558
Change-Id: I3fd779c510ab70d56b1d918f99c20421b524cdc4