regmap: spi: Add missing MODULE_DESCRIPTION()

The modpost script is not happy

  WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/base/regmap/regmap-spi.o

because there is a missing module description.

Add it to the module.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://msgid.link/r/20240410202912.1659275-3-andriy.shevchenko@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/base/regmap/regmap-spi.c

@@ -165,4 +165,5 @@ struct regmap *__devm_regmap_init_spi(struct spi_device *spi,
 }
 EXPORT_SYMBOL_GPL(__devm_regmap_init_spi);
 
+MODULE_DESCRIPTION("regmap SPI Module");
 MODULE_LICENSE("GPL");