tests: Fix header inclusion

When building tests, the path of the library
directory is part of the possible paths for
the includes thus no need to construct it
manually when including headers.

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/tests/suites/test_suite_alignment.function b/tests/suites/test_suite_alignment.function
index b9ceb59..eefbaa5 100644
--- a/tests/suites/test_suite_alignment.function
+++ b/tests/suites/test_suite_alignment.function
@@ -1,5 +1,5 @@
 /* BEGIN_HEADER */
-#include "../library/alignment.h"
+#include <alignment.h>
 
 #include <stdint.h>