kill the 5th argument of generic_file_buffered_write()

same story - it's &iocb->ki_pos in all cases

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --cc fs/ceph/file.c
Simple merge

diff --cc fs/ocfs2/file.c
Simple merge

diff --cc fs/xfs/xfs_file.c
Simple merge

diff --cc include/linux/fs.h
Simple merge

diff --cc mm/filemap.c
Simple merge