power: supply: axp288_fuel_gauge: Fix module autoload

If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/power/supply/axp288_fuel_gauge.ko | grep alias
$

After this patch:

$ modinfo drivers/power/supply/axp288_fuel_gauge.ko | grep alias
alias:          platform:axp288_fuel_gauge
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

drivers/power/supply/axp288_fuel_gauge.c

@@ -1120,6 +1120,7 @@ static const struct platform_device_id axp288_fg_id_table[] = {
 	{ .name = DEV_NAME },
 	{},
 };
+MODULE_DEVICE_TABLE(platform, axp288_fg_id_table);
 
 static int axp288_fuel_gauge_remove(struct platform_device *pdev)
 {