iio: resolver: ad2s1210: remove DRV_NAME macro

The DRV_NAME macro is only used in one place in the ad2s1210 driver and
is not really needed so let's remove it.

Suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231012-ad2s1210-mainline-v1-1-b2ee31c0e9dd@baylibre.com


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