Rename constant-time functions to have mbedtls_ct prefix

Rename functions to better suite with the module name.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 0066744..ab5cdea 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -198,7 +198,7 @@
         /* Check verify-data in constant-time. The length OTOH is no secret */
         if( len    != 1 + ssl->verify_data_len ||
             buf[0] !=     ssl->verify_data_len ||
-            mbedtls_cf_memcmp( buf + 1, ssl->peer_verify_data,
+            mbedtls_ct_memcmp( buf + 1, ssl->peer_verify_data,
                           ssl->verify_data_len ) != 0 )
         {
             MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-matching renegotiation info" ) );
@@ -3582,7 +3582,7 @@
     diff |= peer_pms[1] ^ ver[1];
 
     /* mask = diff ? 0xff : 0x00 using bit operations to avoid branches */
-    mask = mbedtls_cf_uint_mask( diff );
+    mask = mbedtls_ct_uint_mask( diff );
 
     /*
      * Protection against Bleichenbacher's attack: invalid PKCS#1 v1.5 padding
@@ -3665,7 +3665,7 @@
         /* Identity is not a big secret since clients send it in the clear,
          * but treat it carefully anyway, just in case */
         if( n != ssl->conf->psk_identity_len ||
-            mbedtls_cf_memcmp( ssl->conf->psk_identity, *p, n ) != 0 )
+            mbedtls_ct_memcmp( ssl->conf->psk_identity, *p, n ) != 0 )
         {
             ret = MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY;
         }