fuse: only invalidate atime in direct read

After sending a synchronous READ request from __fuse_direct_read() we only
need to invalidate atime; none of the other attributes should be changed by
a read().

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

fs/fuse/file.c

@@ -1419,7 +1419,7 @@ static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
 
 	res = fuse_direct_io(io, iter, ppos, 0);
 
-	fuse_invalidate_attr(inode);
+	fuse_invalidate_atime(inode);
 
 	return res;
 }