No attempt has been made to document any of the demoted functions here

Fixes the following W=1 kernel build warning(s):

 drivers/iio/light/si1145.c:192: warning: Function parameter or member 'data' not described in '__si1145_command_reset'
 drivers/iio/light/si1145.c:228: warning: Function parameter or member 'data' not described in 'si1145_command'
 drivers/iio/light/si1145.c:228: warning: Function parameter or member 'cmd' not described in 'si1145_command'
 drivers/iio/light/si1145.c:1186: warning: Function parameter or member 'trig' not described in 'si1145_trigger_set_state'
 drivers/iio/light/si1145.c:1186: warning: Function parameter or member 'state' not described in 'si1145_trigger_set_state'

Cc: Chuhong Yuan <hslester96@gmail.com>
Cc: Dan Leonard <leonard.crestez@intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>