inputflinger: treat tablet-style inputs as absolute coordinate mouse pointer

inputflinger: treat tablet-style inputs as absolute coordinate mouse pointer

Qemu and VirtualBox use tablet-style inputs. However, it's difficult to
work with the current "invisible finger" or "drag pointer" interface
provided to the virtual absolute coordinate pointing devices.
Instead, this patch classifies them as a regular mouse pointer
(INPUT_DEVICE_CLASS_CURSOR), which is more intuitive to work with.