HID: multitouch: Copyright and note on regression tests

This reflects my new company and officialize the regression tests I'm
conducting between each change.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Acked-by: Henrik Rydberg <rydberg@euromail.se>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>