Add support for Huion v2 protocol tilt reporting. Describe reports as
angles in degrees, which is not exactly true, but there doesn't seem to
be a straightforward, consistent conversion possible, and what's
reported would have to be enough.
Signed-off-by: Nikolai Kondrashov <spbnick@gmail.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>