Tidy-up

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/tests/suites/test_suite_alignment.function b/tests/suites/test_suite_alignment.function
index 3a5038e..b027c4b 100644
--- a/tests/suites/test_suite_alignment.function
+++ b/tests/suites/test_suite_alignment.function
@@ -20,13 +20,8 @@
 
     /* If < 8 bytes, shift right and pad with leading zeros for big-endian */
     if (MBEDTLS_IS_BIG_ENDIAN && olen < 8) {
-        int offset = 8 - olen;
-        for (int i = olen - 1; i >= 0; i--) {
-            raw[i + offset] = raw[i];
-        }
-        for (int i = 0; i < offset; i++) {
-            raw[i] = 0;
-        }
+        memmove(raw + 8 - olen, raw, olen);
+        memset(raw, 0, 8 - olen);
     }
 
     *result = 0;