usb: dwc2: Add comment about BCM2848 ACPI ID

During recent code review the different naming between ACPI and OF
IDs led to confusion. So add a clarifying comment.

Link: https://lore.kernel.org/linux-usb/38e46b44-6248-45e8-bdf9-66008a2fe290@arm.com/
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>

drivers/usb/dwc2/params.c

@@ -332,6 +332,7 @@ const struct of_device_id dwc2_of_match_table[] = {
 MODULE_DEVICE_TABLE(of, dwc2_of_match_table);
 
 const struct acpi_device_id dwc2_acpi_match[] = {
+	/* This ID refers to the same USB IP as of_device_id brcm,bcm2835-usb */
 	{ "BCM2848", (kernel_ulong_t)dwc2_set_bcm_params },
 	{ },
 };