vmstate: stellaris use unused for placeholder entries

Signed-off-by: Juan Quintela <quintela@redhat.com>
diff --git a/hw/stellaris.c b/hw/stellaris.c
index 58aec19..ac9fcc1 100644
--- a/hw/stellaris.c
+++ b/hw/stellaris.c
@@ -290,8 +290,7 @@
         VMSTATE_UINT32(control, gptm_state),
         VMSTATE_UINT32(state, gptm_state),
         VMSTATE_UINT32(mask, gptm_state),
-        VMSTATE_UINT32(mode[0], gptm_state),
-        VMSTATE_UINT32(mode[0], gptm_state),
+        VMSTATE_UNUSED(8),
         VMSTATE_UINT32_ARRAY(load, gptm_state, 2),
         VMSTATE_UINT32_ARRAY(match, gptm_state, 2),
         VMSTATE_UINT32_ARRAY(prescale, gptm_state, 2),