regulator: fan53880: Add support for COMPILE_TEST

This patch adds support for COMPILE_TEST while fixing a warning when
no support for device tree is there.

Reported-by: kernel test robot <[e-mail]>
Signed-off-by: Christoph Fritz <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

drivers/regulator/Kconfig

···
 
 config REGULATOR_FAN53880
 	tristate "Fairchild FAN53880 Regulator"
-	depends on I2C
+	depends on I2C && (OF || COMPILE_TEST)
 	select REGMAP_I2C
 	help
 	  This driver supports Fairchild (ON Semiconductor) FAN53880

drivers/regulator/fan53880.c

···
 	return 0;
 }
 
+#ifdef CONFIG_OF
 static const struct of_device_id fan53880_dt_ids[] = {
 	{ .compatible = "onnn,fan53880", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, fan53880_dt_ids);
+#endif
 
 static const struct i2c_device_id fan53880_i2c_id[] = {
 	{ "fan53880", },