Fixes the following W=1 kernel build warning(s):

 drivers/input/touchscreen/surface3_spi.c: In function ‘surface3_spi_process_touch’:
 drivers/input/touchscreen/surface3_spi.c:97:6: warning: variable ‘timestamp’ set but not used [-Wunused-but-set-variable]

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Henrik Rydberg <rydberg@bitmath.org>
Cc: Benjamin Tissoires <redacted>
Cc: linux-input@vger.kernel.org
Signed-off-by: Lee Jones <redacted>
---
 drivers/input/touchscreen/surface3_spi.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/input/touchscreen/surface3_spi.c b/drivers/input/touchscreen/surface3_spi.c
index ce4828b1415a8..72dc4c562a4e1 100644
--- a/drivers/input/touchscreen/surface3_spi.c
+++ b/drivers/input/touchscreen/surface3_spi.c

@@ -94,9 +94,7 @@ static void surface3_spi_report_touch(struct surface3_ts_data *ts_data,
 
 static void surface3_spi_process_touch(struct surface3_ts_data *ts_data, u8 *data)
 {
-	u16 timestamp;
 	unsigned int i;
-	timestamp = get_unaligned_le16(&data[15]);