crypto_config: Migrated MBEDTLS_NULL_CIPHER in legacy-crypto

Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
diff --git a/docs/proposed/config-split.md b/docs/proposed/config-split.md
index b91d55e..9f8d734 100644
--- a/docs/proposed/config-split.md
+++ b/docs/proposed/config-split.md
@@ -311,6 +311,7 @@
 #define MBEDTLS_CIPHER_MODE_CTR
 #define MBEDTLS_CIPHER_MODE_OFB
 #define MBEDTLS_CIPHER_MODE_XTS
+//#define MBEDTLS_CIPHER_NULL_CIPHER
 #define MBEDTLS_CIPHER_PADDING_ONE_AND_ZEROS
 #define MBEDTLS_CIPHER_PADDING_PKCS7
 #define MBEDTLS_CIPHER_PADDING_ZEROS
@@ -382,7 +383,6 @@
 
 #### SECTION TLS feature selection
 ```
-//#define MBEDTLS_CIPHER_NULL_CIPHER
 #define MBEDTLS_DEBUG_C
 #define MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED
 #define MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED
diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index c4d6215..6096a3f 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -50,35 +50,6 @@
 //#define MBEDTLS_TIMING_ALT
 
 /**
- * \def MBEDTLS_CIPHER_NULL_CIPHER
- *
- * Enable NULL cipher.
- * Warning: Only do so when you know what you are doing. This allows for
- * encryption or channels without any security!
- *
- * To enable the following ciphersuites:
- *      MBEDTLS_TLS_ECDH_ECDSA_WITH_NULL_SHA
- *      MBEDTLS_TLS_ECDH_RSA_WITH_NULL_SHA
- *      MBEDTLS_TLS_ECDHE_ECDSA_WITH_NULL_SHA
- *      MBEDTLS_TLS_ECDHE_RSA_WITH_NULL_SHA
- *      MBEDTLS_TLS_ECDHE_PSK_WITH_NULL_SHA384
- *      MBEDTLS_TLS_ECDHE_PSK_WITH_NULL_SHA256
- *      MBEDTLS_TLS_ECDHE_PSK_WITH_NULL_SHA
- *      MBEDTLS_TLS_DHE_PSK_WITH_NULL_SHA384
- *      MBEDTLS_TLS_DHE_PSK_WITH_NULL_SHA256
- *      MBEDTLS_TLS_DHE_PSK_WITH_NULL_SHA
- *      MBEDTLS_TLS_RSA_WITH_NULL_SHA256
- *      MBEDTLS_TLS_RSA_WITH_NULL_SHA
- *      MBEDTLS_TLS_RSA_WITH_NULL_MD5
- *      MBEDTLS_TLS_PSK_WITH_NULL_SHA384
- *      MBEDTLS_TLS_PSK_WITH_NULL_SHA256
- *      MBEDTLS_TLS_PSK_WITH_NULL_SHA
- *
- * Uncomment this macro to enable the NULL cipher and ciphersuites
- */
-//#define MBEDTLS_CIPHER_NULL_CIPHER
-
-/**
  * \def MBEDTLS_KEY_EXCHANGE_PSK_ENABLED
  *
  * Enable the PSK based ciphersuite modes in SSL / TLS.
diff --git a/tf-psa-crypto/include/psa/crypto_config.h b/tf-psa-crypto/include/psa/crypto_config.h
index 5f92ae7..45c7bde 100644
--- a/tf-psa-crypto/include/psa/crypto_config.h
+++ b/tf-psa-crypto/include/psa/crypto_config.h
@@ -2174,6 +2174,35 @@
 #define MBEDTLS_CIPHER_MODE_XTS
 
 /**
+ * \def MBEDTLS_CIPHER_NULL_CIPHER
+ *
+ * Enable NULL cipher.
+ * Warning: Only do so when you know what you are doing. This allows for
+ * encryption or channels without any security!
+ *
+ * To enable the following ciphersuites:
+ *      MBEDTLS_TLS_ECDH_ECDSA_WITH_NULL_SHA
+ *      MBEDTLS_TLS_ECDH_RSA_WITH_NULL_SHA
+ *      MBEDTLS_TLS_ECDHE_ECDSA_WITH_NULL_SHA
+ *      MBEDTLS_TLS_ECDHE_RSA_WITH_NULL_SHA
+ *      MBEDTLS_TLS_ECDHE_PSK_WITH_NULL_SHA384
+ *      MBEDTLS_TLS_ECDHE_PSK_WITH_NULL_SHA256
+ *      MBEDTLS_TLS_ECDHE_PSK_WITH_NULL_SHA
+ *      MBEDTLS_TLS_DHE_PSK_WITH_NULL_SHA384
+ *      MBEDTLS_TLS_DHE_PSK_WITH_NULL_SHA256
+ *      MBEDTLS_TLS_DHE_PSK_WITH_NULL_SHA
+ *      MBEDTLS_TLS_RSA_WITH_NULL_SHA256
+ *      MBEDTLS_TLS_RSA_WITH_NULL_SHA
+ *      MBEDTLS_TLS_RSA_WITH_NULL_MD5
+ *      MBEDTLS_TLS_PSK_WITH_NULL_SHA384
+ *      MBEDTLS_TLS_PSK_WITH_NULL_SHA256
+ *      MBEDTLS_TLS_PSK_WITH_NULL_SHA
+ *
+ * Uncomment this macro to enable the NULL cipher and ciphersuites
+ */
+//#define MBEDTLS_CIPHER_NULL_CIPHER
+
+/**
  * \def MBEDTLS_CIPHER_PADDING_PKCS7
  *
  * MBEDTLS_CIPHER_PADDING_XXX: Uncomment or comment macros to add support for