HID: uclogic: Replace pen_frame_flag with subreport_list

Replace a single pen_frame_flag in struct uclogic_params with
subreport_list in struct uclogic_params_pen to prepare for handling more
subreports in Huion HS610.

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>