Add missing copyright dates to scripts and sources

To find any files with a missing copyright declaration, use the following script:

# ========================
#!/bin/sh

# Find files with copyright declarations, and list their file extensions
exts=$(grep -Ril --exclude-dir .git --exclude-dir 3rdparty\
                 --exclude-dir programs/fuzz 'Copyright.*Arm' | sed '
  s/.*\///
  s/.*\./*./
  s/.*/-name "&"/
' | sort -u | sed -n '
  :l
    N
    $!bl
  s/\n/ -o /gp
')

# Find files with file extensions that ususally include copyright extensions,
# but don't include a copyright declaration themselves.
eval "find\
  '(' -path './.git' -o -path './3rdparty' -o -path './programs/fuzz' ')' -prune\
  -o ! -path './tests/data_files/format_pkcs12.fmt'\
     ! -path './programs/psa/psa_constant_names_generated.c'\
     '(' $exts ')' -print" | xargs grep -Li 'Copyright.*Arm'
# ========================

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
diff --git a/tests/scripts/gen_ctr_drbg.pl b/tests/scripts/gen_ctr_drbg.pl
index 3c074be..624da22 100755
--- a/tests/scripts/gen_ctr_drbg.pl
+++ b/tests/scripts/gen_ctr_drbg.pl
@@ -3,6 +3,10 @@
 # Based on NIST CTR_DRBG.rsp validation file
 # Only uses AES-256-CTR cases that use a Derivation function
 # and concats nonce and personalization for initialization.
+#
+# Copyright (C) 2011, Arm Limited, All Rights Reserved
+#
+# This file is part of Mbed TLS (https://tls.mbed.org)
 
 use strict;