HID: core: add two new usages for digitizer

On Feb 17, 2014, two new usages are approved to HID usage Table 18 -
Digitizer Page:

5A	Secondary Barrel Switch		MC	16.4
5B	Transducer Serial Number	SV	16.3.1

This patch adds relevant definitions to hid/input. It also removes
outdated comments in hid.h.

Signed-off-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 720e3a1..a468ec8 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -233,11 +233,6 @@
 #define HID_DG_BARRELSWITCH	0x000d0044
 #define HID_DG_ERASER		0x000d0045
 #define HID_DG_TABLETPICK	0x000d0046
-/*
- * as of May 20, 2009 the usages below are not yet in the official USB spec
- * but are being pushed by Microsft as described in their paper "Digitizer
- * Drivers for Windows Touch and Pen-Based Computers"
- */
 #define HID_DG_CONFIDENCE	0x000d0047
 #define HID_DG_WIDTH		0x000d0048
 #define HID_DG_HEIGHT		0x000d0049
@@ -246,6 +241,8 @@
 #define HID_DG_DEVICEINDEX	0x000d0053
 #define HID_DG_CONTACTCOUNT	0x000d0054
 #define HID_DG_CONTACTMAX	0x000d0055
+#define HID_DG_BARRELSWITCH2	0x000d005a
+#define HID_DG_TOOLSERIALNUMBER	0x000d005b
 
 /*
  * HID report types --- Ouch! HID spec says 1 2 3!