Revert "fuse: require /dev/fuse reads to have enough buffer capacity"

	unsigned reqsize;

	unsigned int hash;

	/*

	 * Require sane minimum read buffer - that has capacity for fixed part

	 * of any request header + negotated max_write room for data. If the

	 * requirement is not satisfied return EINVAL to the filesystem server

	 * to indicate that it is not following FUSE server/client contract.

	 * Don't dequeue / abort any request.

	 */

	if (nbytes < max_t(size_t, FUSE_MIN_READ_BUFFER, 4096 + fc->max_write))

		return -EINVAL;

 restart:

	spin_lock(&fiq->waitq.lock);

	err = -EAGAIN;