iio: accel: bmi088: Use EXPORT_NS_GPL_RUNTIME_DEV_PM_OPS() and pm_ptr()

iio: accel: bmi088: Use EXPORT_NS_GPL_RUNTIME_DEV_PM_OPS() and pm_ptr()

These macros allow the compiler to remove unused pm ops functions without
needing to mark them maybe unused.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: LI Qingwu <Qing-wu.Li@leica-geosystems.com.cn>
Cc: Mike Looijmans <mike.looijmans@topic.nl>
Link: https://lore.kernel.org/r/20220807185618.1038812-6-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>