iio: chemical: sps30: Move symbol exports into IIO_SPS30 namespace

Avoid unnecessary pollution of the global symbol namespace by
moving library functions in to a specific namespace and import
that into the drivers that make use of the functions.

For more info: https://lwn.net/Articles/760045/Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Tomasz Duszynski <tomasz.duszynski@octakon.com>
Link: https://lore.kernel.org/r/20220220173701.502331-4-jic23@kernel.orgReviewed-By: Joe Simmons-Talbott <joetalbott@gmail.com>
Link: https://lore.kernel.org/r/20220604155306.422937-4-jic23@kernel.orgSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/chemical/sps30.c

@@ -372,7 +372,7 @@ int sps30_probe(struct device *dev, const char *name, void *priv, const struct s
 
 	return devm_iio_device_register(dev, indio_dev);
 }
-EXPORT_SYMBOL_GPL(sps30_probe);
+EXPORT_SYMBOL_NS_GPL(sps30_probe, IIO_SPS30);
 
 MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
 MODULE_DESCRIPTION("Sensirion SPS30 particulate matter sensor driver");

drivers/iio/chemical/sps30_i2c.c

@@ -256,3 +256,4 @@ module_i2c_driver(sps30_i2c_driver);
 MODULE_AUTHOR("Tomasz Duszynski <tomasz.duszynski@octakon.com>");
 MODULE_DESCRIPTION("Sensirion SPS30 particulate matter sensor i2c driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(IIO_SPS30);

drivers/iio/chemical/sps30_serial.c

@@ -429,3 +429,4 @@ module_serdev_device_driver(sps30_serial_driver);
 MODULE_AUTHOR("Tomasz Duszynski <tomasz.duszynski@octakon.com>");
 MODULE_DESCRIPTION("Sensirion SPS30 particulate matter sensor serial driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(IIO_SPS30);