chore: update to use Arm word across TF-A

Align entire TF-A to use Arm in copyright header.

Change-Id: Ief9992169efdab61d0da6bd8c5180de7a4bc2244
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
diff --git a/lib/compiler-rt/compiler-rt.mk b/lib/compiler-rt/compiler-rt.mk
index b41c4d0..2b16504 100644
--- a/lib/compiler-rt/compiler-rt.mk
+++ b/lib/compiler-rt/compiler-rt.mk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2017-2019, Arm Limited and Contributors. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are met: