fix(fdts stm32mp1): correct copyright dates

Add 2021 year in the file header Copyright line.

Change-Id: I09f7bef1f746c429ff308286169354e58648a1cd
Signed-off-by: Yann Gautier <yann.gautier@st.com>
diff --git a/fdts/stm32mp15-ddr3-1x4Gb-1066-binG.dtsi b/fdts/stm32mp15-ddr3-1x4Gb-1066-binG.dtsi
index 6ca6293..c6d6434 100644
--- a/fdts/stm32mp15-ddr3-1x4Gb-1066-binG.dtsi
+++ b/fdts/stm32mp15-ddr3-1x4Gb-1066-binG.dtsi
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
 /*
- * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
+ * Copyright (c) 2018-2021, STMicroelectronics - All Rights Reserved
  */
 
 /*