This should be a no-op now, but once inode writeback works, it'll be
necessary to have the correct attribute in the dirty inode.

Previously the attribute fetch timeout was marked invalid and the server
provided the updated attribute.  When the inode is dirty, the server
cannot be consulted since it does not yet know the pending setattr.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>