sim: Update Linaro copyrights

Update to current year for files modified.

Signed-off-by: David Brown <david.brown@linaro.org>
diff --git a/sim/src/image.rs b/sim/src/image.rs
index 4ee9ddd..44f628b 100644
--- a/sim/src/image.rs
+++ b/sim/src/image.rs
@@ -1,4 +1,4 @@
-// Copyright (c) 2019 Linaro LTD
+// Copyright (c) 2019-2021 Linaro LTD
 // Copyright (c) 2019-2020 JUUL Labs
 // Copyright (c) 2019-2021 Arm Limited
 //