lm832x: make fields to have the same types that they are saved/loaded They were saved as uint8_t already. To make things simpler, I just reg == -1 used to indicate an error, I create LM832x_GENERAL_ERROR with vale 0xff to represet it Signed-off-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>