media: rc-core: rename input_name to device_name

When an ir-spi is registered, you get this message.

rc rc0: Unspecified device as /devices/platform/soc/3f215080.spi/spi_master/spi32766/spi32766.128/rc/rc0

"Unspecified device" refers to input_name, which makes no sense for IR
TX only devices. So, rename to device_name.

Also make driver_name const char* so that no casts are needed anywhere.

Now ir-spi reports:

rc rc0: IR SPI as /devices/platform/soc/3f215080.spi/spi_master/spi32766/spi32766.128/rc/rc0

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
diff --git a/drivers/media/pci/saa7134/saa7134-input.c b/drivers/media/pci/saa7134/saa7134-input.c
index 78849c1..ba1fc77 100644
--- a/drivers/media/pci/saa7134/saa7134-input.c
+++ b/drivers/media/pci/saa7134/saa7134-input.c
@@ -870,7 +870,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
 	if (raw_decode)
 		rc->driver_type = RC_DRIVER_IR_RAW;
 
-	rc->input_name = ir->name;
+	rc->device_name = ir->name;
 	rc->input_phys = ir->phys;
 	rc->input_id.bustype = BUS_PCI;
 	rc->input_id.version = 1;