Fix code style issues

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/tests/src/helpers.c b/tests/src/helpers.c
index 85345d8..49a7df2 100644
--- a/tests/src/helpers.c
+++ b/tests/src/helpers.c
@@ -147,7 +147,7 @@
 void mbedtls_test_set_step(unsigned long step)
 {
     /* Internal function only - mbedtls_test_info_mutex should be held prior
-         * to calling this function. */
+     * to calling this function. */
 
     mbedtls_test_info.step = step;
 }
@@ -168,7 +168,7 @@
 void mbedtls_test_set_line1(const char *line)
 {
     /* Internal function only - mbedtls_test_info_mutex should be held prior
-         * to calling this function. */
+     * to calling this function. */
 
     if (line == NULL) {
         memset(mbedtls_test_info.line1, 0, MBEDTLS_TEST_LINE_LENGTH);
@@ -193,7 +193,7 @@
 void mbedtls_test_set_line2(const char *line)
 {
     /* Internal function only - mbedtls_test_info_mutex should be held prior
-         * to calling this function. */
+     * to calling this function. */
 
     if (line == NULL) {
         memset(mbedtls_test_info.line2, 0, MBEDTLS_TEST_LINE_LENGTH);
@@ -245,7 +245,7 @@
 void mbedtls_test_set_case_uses_negative_0(unsigned uses)
 {
     /* Internal function only - mbedtls_test_info_mutex should be held prior
-         * to calling this function. */
+     * to calling this function. */
 
     mbedtls_test_info.case_uses_negative_0 = uses;
 }