qtest: Be paranoid about accept() addrlen argument POSIX specifies that address_len shall on output specify the length of the stored address; it does not however specify whether it may get updated on failure as well to, e.g., zero. In case EINTR occurs, re-initialize the variable to the desired value. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>