staging: atomicsp: fix a loop timeout

It's a post-op loop so we timeout with "max_wait" set to -1, not 0.

Fixes: a49d2536 ("staging/atomisp: Add support for the Intel IPU v2")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>