Use invalidate_inode_pages2 that don't leave pages even if shrink_page_list()
has a temp ref on them. It prevents a data coherency problem when
cifs_invalidate_mapping didn't invalidate pages but the client thinks that a data
from the cache is uptodate according to an oplock level (exclusive or II).
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>