media: cxd2880: don't return unitialized values

drivers/media/dvb-frontends/cxd2880/cxd2880_devio_spi.c:59 cxd2880_io_spi_read_reg() error: uninitialized symbol 'ret'.
drivers/media/dvb-frontends/cxd2880/cxd2880_devio_spi.c:111 cxd2880_io_spi_write_reg() error: uninitialized symbol 'ret'.
drivers/media/dvb-frontends/cxd2880/cxd2880_tnrdmd.c:2985 cxd2880_tnrdmd_set_cfg() error: uninitialized symbol 'ret'.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/dvb-frontends/cxd2880/cxd2880_devio_spi.c

@@ -16,7 +16,7 @@ static int cxd2880_io_spi_read_reg(struct cxd2880_io *io,
 				   u8 sub_address, u8 *data,
 				   u32 size)
 {
-	int ret;
+	int ret = 0;
 	struct cxd2880_spi *spi = NULL;
 	u8 send_data[6];
 	u8 *read_data_top = data;
@@ -64,7 +64,7 @@ static int cxd2880_io_spi_write_reg(struct cxd2880_io *io,
 				    u8 sub_address,
 				    const u8 *data, u32 size)
 {
-	int ret;
+	int ret = 0;
 	struct cxd2880_spi *spi = NULL;
 	u8 send_data[BURST_WRITE_MAX + 4];
 	const u8 *write_data_top = data;

drivers/media/dvb-frontends/cxd2880/cxd2880_tnrdmd.c

@@ -2503,7 +2503,7 @@ int cxd2880_tnrdmd_set_cfg(struct cxd2880_tnrdmd *tnr_dmd,
 			   enum cxd2880_tnrdmd_cfg_id id,
 			   int value)
 {
-	int ret;
+	int ret = 0;
 	u8 data[2] = { 0 };
 	u8 need_sub_setting = 0;