HID: logitech-hidpp: remove double assignment from __hidpp_send_report

The hidpp variable is already initialized with hid_get_drvdata(hdev)
when it is declared, drop the second no-op assignment.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>