Input: ALPS - add support for model found on Dell XT2

This patch adds support for touchpad found on Dell XT2. It's a dual device
with device ID: 73, 00, 14, that comply with "ALPS_PROTO_V2".
Signed-off-by: Yunkang Tang <yunkang.tang@cn.alps.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/mouse/alps.c

@@ -103,6 +103,7 @@ static const struct alps_model_info alps_model_data[] = {
 	/* Dell Latitude E5500, E6400, E6500, Precision M4400 */
 	{ { 0x62, 0x02, 0x14 }, 0x00, ALPS_PROTO_V2, 0xcf, 0xcf,
 		ALPS_PASS | ALPS_DUALPOINT | ALPS_PS2_INTERLEAVED },
+	{ { 0x73, 0x00, 0x14 }, 0x00, ALPS_PROTO_V2, 0xcf, 0xcf, ALPS_DUALPOINT },		/* Dell XT2 */
 	{ { 0x73, 0x02, 0x50 }, 0x00, ALPS_PROTO_V2, 0xcf, 0xcf, ALPS_FOUR_BUTTONS },		/* Dell Vostro 1400 */
 	{ { 0x52, 0x01, 0x14 }, 0x00, ALPS_PROTO_V2, 0xff, 0xff,
 		ALPS_PASS | ALPS_DUALPOINT | ALPS_PS2_INTERLEAVED },				/* Toshiba Tecra A11-11L */