HID: rmi: do not handle touchscreens through hid-rmi

Currently, hid-rmi drives every Synaptics product, but the touchscreens
on the Windows tablets should be handled through hid-multitouch.

Instead of providing a long list of PIDs, rely on the scan_report
capability to detect which should go to hid-multitouch, and which
should not go to hid-rmi.

related bug:
https://bugzilla.kernel.org/show_bug.cgi?id=74241
https://bugzilla.redhat.com/show_bug.cgi?id=1089583

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

include/linux/hid.h

@@ -299,12 +299,20 @@ struct hid_item {
 
 /*
  * HID device groups
+ *
+ * Note: HID_GROUP_ANY is declared in linux/mod_devicetable.h
+ * and has a value of 0x0000
  */
 #define HID_GROUP_GENERIC			0x0001
 #define HID_GROUP_MULTITOUCH			0x0002
 #define HID_GROUP_SENSOR_HUB			0x0003
 #define HID_GROUP_MULTITOUCH_WIN_8		0x0004
 
+/*
+ * Vendor specific HID device groups
+ */
+#define HID_GROUP_RMI				0x0100
+
 /*
  * This is the global environment of the parser. This information is
  * persistent for main-items. The global environment can be saved and