Rename HexParam_t -> data_t for consistent coding style
diff --git a/tests/suites/test_suite_arc4.function b/tests/suites/test_suite_arc4.function
index 2a56a5b..ae3b032 100644
--- a/tests/suites/test_suite_arc4.function
+++ b/tests/suites/test_suite_arc4.function
@@ -8,8 +8,8 @@
  */
 
 /* BEGIN_CASE */
-void mbedtls_arc4_crypt( HexParam_t * src_str, HexParam_t * key_str,
-                         HexParam_t * hex_dst_string )
+void mbedtls_arc4_crypt( data_t * src_str, data_t * key_str,
+                         data_t * hex_dst_string )
 {
     unsigned char dst_str[1000];
     mbedtls_arc4_context ctx;