iio: common: ms_sensors: ms_sensors_i2c: Fix misspelling of parameter 'client'

Probably due to docrot.

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

 drivers/iio/common/ms_sensors/ms_sensors_i2c.c:186: warning: Function parameter or member 'client' not described in 'ms_sensors_read_serial'
 drivers/iio/common/ms_sensors/ms_sensors_i2c.c:186: warning: Excess function parameter 'cli' description in 'ms_sensors_read_serial'

Cc: William Markezana <william.markezana@meas-spec.com>
Cc: Ludovic Tancerel <ludovic.tancerel@maplehightech.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>