tests/aio.c: include <time.h>

* tests/aio.c: Include <time.h> for struct timespec.

Reported-by: Szabolcs Nagy <nsz@port70.net>
diff --git a/tests/aio.c b/tests/aio.c
index 08974e1..e3a073a 100644
--- a/tests/aio.c
+++ b/tests/aio.c
@@ -33,6 +33,7 @@
 #include <errno.h>
 #include <inttypes.h>
 #include <stdio.h>
+#include <time.h>
 #include <unistd.h>
 #include <sys/fcntl.h>
 #include <sys/syscall.h>