[media] cx18: fix kernel oops with tda8290 tuner

This was caused by an uninitialized setup.config field.

Based on a suggestion from Devin Heitmueller.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Thanks-to: Devin Heitmueller <dheitmueller@kernellabs.com>
Reported-by: Scott Robinson <scott.robinson55@gmail.com>
Tested-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: stable@vger.kernel.org      # for v3.10 and up
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/pci/cx18/cx18-driver.c

@@ -1091,6 +1091,7 @@ static int cx18_probe(struct pci_dev *pci_dev,
 		setup.addr = ADDR_UNSET;
 		setup.type = cx->options.tuner;
 		setup.mode_mask = T_ANALOG_TV;  /* matches TV tuners */
+		setup.config = NULL;
 		if (cx->options.radio > 0)
 			setup.mode_mask |= T_RADIO;
 		setup.tuner_callback = (setup.type == TUNER_XC2028) ?