ARM: shmobile: rcar-gen2: Drop comma after OF match table sentinel

It does not make sense to have a comma after a sentinel, as any new
elements must be added before the sentinel.

Add a comment to clarify the purpose of the empty element.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/baaa4df6284401eb126573eb1c8ea5a88705cc37.1646311858.git.geert+renesas@glider.be

Author: geertu

arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c

@@ -67,7 +67,7 @@ static const struct of_device_id rcar_gen2_quirk_match[] = {
 	{ .compatible = "dlg,da9063", .data = &da9063_msg },
 	{ .compatible = "dlg,da9063l", .data = &da9063_msg },
 	{ .compatible = "dlg,da9210", .data = &da9210_msg },
-	{},
+	{ /* sentinel */ }
 };
 
 static int regulator_quirk_notify(struct notifier_block *nb,