iio: bu27034: Fix integration time

The bu27034 uses micro seconds for integration time configuration. This
is incorrect as the ABI mandates use of seconds.

Change BU27034 driver to use seconds for integration time.

Fixes: e52afbd6 ("iio: light: ROHM BU27034 Ambient Light Sensor")
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://lore.kernel.org/r/a05647669af22ba919c7c87dccb43975e3235a87.1681722914.git.mazziesaccount@gmail.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>