nbd: Remove 'harderror' and propagate error properly
nbd: Remove 'harderror' and propagate error properly

Instead of a variable 'harderror' we can simply try to correctly
propagate errors to the userspace.

This patch removes the harderror variable and passes errors through
error pointers and nbd_do_it back to the userspace.

Signed-off-by: Markus Pargmann <b9e0f7aed71fa470d5913fb2df2da788a8fb0eb2@pengutronix.de>
Acked-by: Pavel Machek <2375fa63e2908bb2df59f606483a3aa92321db7a@ucw.cz>
Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@fb.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs