Input: ALPS - remove unused argument to alps_enter_command_mode()

Now that alps_identify() explicitly issues an EC report using
alps_rpt_cmd(), we no longer need to look at the magic numbers returned
by alps_enter_command_mode().

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>