test: Add NDEBUG sanity check

Hopefully stops people tripping over themselves if NDEBUG gets defined.

Change-Id: Iafb81d01f6451619f49a5030e5154c8f30ffebdb
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/test/sanity.c b/test/sanity.c
new file mode 100644
index 0000000..b4989f8
--- /dev/null
+++ b/test/sanity.c
@@ -0,0 +1,8 @@
+int main(void)
+{
+#ifdef NDEBUG
+	return 1;
+#else
+	return 0;
+#endif
+}