Always use bundled liburing.h for test cases

Don't rely on the systems version, or that the system even has one
installed.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/test/accept.c b/test/accept.c
index c47c2f5..edb7bc2 100644
--- a/test/accept.c
+++ b/test/accept.c
@@ -17,7 +17,7 @@
 #include <netinet/tcp.h>
 #include <netinet/in.h>
 
-#include <liburing.h>
+#include "liburing.h"
 
 static int no_accept;