We should be returning negative error codes here or it leads to a crash.
This also silences a static checker warning.
	drivers/media/pci/mantis/mantis_cards.c:250 mantis_pci_probe()
	warn: 'mantis->dmxdev.dvbdev->fops' double freed
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
                        goto err5;
                } else {
                        if (mantis->fe == NULL) {
+                               result = -ENOMEM;
                                dprintk(MANTIS_ERROR, 1, "FE <NULL>");
                                goto err5;
                        }
-
-                       if (dvb_register_frontend(&mantis->dvb_adapter, mantis->fe)) {
+                       result = dvb_register_frontend(&mantis->dvb_adapter, mantis->fe);
+                       if (result) {
                                dprintk(MANTIS_ERROR, 1, "ERROR: Frontend registration failed");
 
                                if (mantis->fe->ops.release)