Input: wacom - add product id used by Samsung Slate 7

New product ID reported by Harvey Braun on linuxwacom mailing list
and also tested this patch with new hardware.
Signed-off-by: Chris Bagwell <chris@cnpbagwell.com>
Acked-by: Ping Cheng <pinglinux@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/tablet/wacom_wac.c

@@ -1470,6 +1470,9 @@ static const struct wacom_features wacom_features_0xE3 =
 static const struct wacom_features wacom_features_0xE6 =
 	{ "Wacom ISDv4 E6",       WACOM_PKGLEN_TPC2FG,    27760, 15694,  255,
 	  0, TABLETPC2FG, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
+static const struct wacom_features wacom_features_0xEC =
+	{ "Wacom ISDv4 EC",       WACOM_PKGLEN_GRAPHIRE,  25710, 14500,  255,
+	  0, TABLETPC,    WACOM_INTUOS_RES, WACOM_INTUOS_RES };
 static const struct wacom_features wacom_features_0x47 =
 	{ "Wacom Intuos2 6x8",    WACOM_PKGLEN_INTUOS,    20320, 16240, 1023,
 	  31, INTUOS, WACOM_INTUOS_RES, WACOM_INTUOS_RES };
@@ -1611,6 +1614,7 @@ const struct usb_device_id wacom_ids[] = {
 	{ USB_DEVICE_WACOM(0xE2) },
 	{ USB_DEVICE_WACOM(0xE3) },
 	{ USB_DEVICE_WACOM(0xE6) },
+	{ USB_DEVICE_WACOM(0xEC) },
 	{ USB_DEVICE_WACOM(0x47) },
 	{ USB_DEVICE_LENOVO(0x6004) },
 	{ }