HID: wacom: remove unused hid_data::pressure

The pressure member in struct hid_data is unused. It was
added in commit 5ae6e89f7409 (HID: wacom: implement the finger part of
the HID generic handling), but never used.

As this is not a struct to communicate with the HW, remove that member.

Found by https://github.com/jirislaby/clang-struct.

Signed-off-by: Jiri Slaby (SUSE) <[e-mail]>
Cc: Ping Cheng <[e-mail]>
Cc: Jason Gerecke <[e-mail]>
Cc: Jiri Kosina <[e-mail]>
Cc: Benjamin Tissoires <[e-mail]>
Acked-by: Ping Cheng <[e-mail]>
Signed-off-by: Jiri Kosina <[e-mail]>

drivers/hid/wacom_wac.h

···
 	bool confidence;
 	int x;
 	int y;
-	int pressure;
 	int width;
 	int height;
 	int id;