backlight: ili922x: Remove redundant variable len

The variable len is assigned but never read, therefore it is redundant
and can be removed. Cleans up clang warning:

drivers/video/backlight/ili922x.c:276:2: warning: Value stored to 'len'
is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/video/backlight/ili922x.c

@@ -251,7 +251,7 @@ static int ili922x_write(struct spi_device *spi, u8 reg, u16 value)
 	struct spi_transfer xfer_regindex, xfer_regvalue;
 	unsigned char tbuf[CMD_BUFSIZE];
 	unsigned char rbuf[CMD_BUFSIZE];
-	int ret, len = 0;
+	int ret;
 
 	memset(&xfer_regindex, 0, sizeof(struct spi_transfer));
 	memset(&xfer_regvalue, 0, sizeof(struct spi_transfer));
@@ -273,7 +273,6 @@ static int ili922x_write(struct spi_device *spi, u8 reg, u16 value)
 	ret = spi_sync(spi, &msg);
 
 	spi_message_init(&msg);
-	len = 0;
 	tbuf[0] = set_tx_byte(START_BYTE(ili922x_id, START_RS_REG,
 					 START_RW_WRITE));
 	tbuf[1] = set_tx_byte((value & 0xFF00) >> 8);