backlight: da9052: Fix module autoload

The driver has a platform device ID table with multiple device entries,
each setting a different register address in its driver_data to control
the WLED brightness.

But the driver doesn't export these as aliases with MODULE_DEVICE_TABLE()
when the driver is built as a module, instead it just has a single alias
using MODULE_ALIAS("platform:da9052-backlight"). That is clearly wrong
since there isn't a "da9052-backlight" in the platform device ID table,
so if that device name is used, the device won't even match the driver.

So instead of having a wrong alias, export the ones in the dev ID table.

Before this patch:

$ modinfo drivers/video/backlight/da9052_bl.ko | grep alias
alias: platform:da9052-backlight

After this patch:

$ modinfo drivers/video/backlight/da9052_bl.ko | grep alias
alias: platform:da9052-wled3
alias: platform:da9052-wled2
alias: platform:da9052-wled1

Signed-off-by: Javier Martinez Canillas <[e-mail]>
Acked-by: Adam Thomson <[e-mail]>
Acked-by: Jingoo Han <[e-mail]>
Signed-off-by: Lee Jones <[e-mail]>

drivers/video/backlight/da9052_bl.c

···
 	},
 	{ },
 };
+MODULE_DEVICE_TABLE(platform, da9052_wled_ids);
 
 static struct platform_driver da9052_wled_driver = {
 	.probe		= da9052_backlight_probe,
···
 MODULE_AUTHOR("David Dajun Chen <[e-mail]>");
 MODULE_DESCRIPTION("Backlight driver for DA9052 PMIC");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:da9052-backlight");