ACPI: IORT: Add extra message "applying workaround" for off-by-1 issue

As we already applied a workaround for the off-by-1 issue,
it's good to add extra message "applying workaround" to make
people less uneasy to see FW_BUG message in the boot log.

Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/1588910198-8348-1-git-send-email-guohanjun@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index b011d25..6e445bc 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -332,6 +332,8 @@ static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in,
 		       map, rid_in);
 		if (rid_in != map->input_base)
 			return -ENXIO;
+
+		pr_err(FW_BUG "applying workaround.\n");
 	}
 
 	*rid_out = map->output_base + (rid_in - map->input_base);