change test function includes to use one convention
diff --git a/tests/suites/test_suite_ctr_drbg.function b/tests/suites/test_suite_ctr_drbg.function
index c9cb22e..644eb46 100644
--- a/tests/suites/test_suite_ctr_drbg.function
+++ b/tests/suites/test_suite_ctr_drbg.function
@@ -1,7 +1,5 @@
 /* BEGIN_HEADER */
-#include <polarssl/ctr_drbg.h>
-
-#include <string.h>
+#include "polarssl/ctr_drbg.h"
 
 int test_offset_idx;
 int entropy_func( void *data, unsigned char *buf, size_t len )