[media] dib8000: Fix: add missing 4K FFT mode

Without that, tuning may fail on 4K FFT mode, as the transmission
parameter cache will be initialized with a wrong value.
Acked-By: Patrick Boettcher <pboettcher@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/dvb-frontends/dib8000.c

@@ -3432,6 +3432,9 @@ static int dib8000_get_frontend(struct dvb_frontend *fe)
 	case 1:
 		fe->dtv_property_cache.transmission_mode = TRANSMISSION_MODE_2K;
 		break;
+	case 2:
+		fe->dtv_property_cache.transmission_mode = TRANSMISSION_MODE_4K;
+		break;
 	case 3:
 	default:
 		fe->dtv_property_cache.transmission_mode = TRANSMISSION_MODE_8K;