input: Adjust input_pointing_device_subtype enumeration and usages.

Follow input_device_type above: we don't have _TYPE or _SUBTYPE on
the end, but _POINTING in the middle, because these aren't in a global
"subtype" enumeration, but a B_POINTING_DEVICE-specific enumeration.

Also don't bother adding the UNKNOWN type to messages that have no
type; if it's not included, UNKNOWN is implied. Saves a few CPU cycles.

Change-Id: I9088b9fcee63bf001b43febbe1e3ac17eb1792b4
Reviewed-on: https://review.haiku-os.org/c/haiku/+/8635
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: waddlesplash <[email protected]>

headers/os/interface/Input.h

@@ -26,10 +26,10 @@ enum input_device_type {
 
 
 enum input_pointing_device_subtype {
-	B_UNKNOWN_DEVICE_SUBTYPE	= 0,
-	B_MOUSE_DEVICE_SUBTYPE		= 1,
-	B_TOUCHPAD_DEVICE_SUBTYPE	= 2,
-	B_TABLET_DEVICE_SUBTYPE		= 3
+	B_UNKNOWN_POINTING_DEVICE	= 0,
+	B_MOUSE_POINTING_DEVICE		= 1,
+	B_TOUCHPAD_POINTING_DEVICE	= 2,
+	B_TABLET_POINTING_DEVICE	= 3
 };