hw/pl110.c: Add post-load hook to invalidate display

Add a post-load hook which invalidates the display. In particular, if we
don't do this and the display size we've just reloaded is larger than
the default then we will segfault trying to read off the end of the buffer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/pl110.c

@@ -60,10 +60,13 @@ typedef struct {
     qemu_irq irq;
 } pl110_state;
 
+static int vmstate_pl110_post_load(void *opaque, int version_id);
+
 static const VMStateDescription vmstate_pl110 = {
     .name = "pl110",
     .version_id = 2,
     .minimum_version_id = 1,
+    .post_load = vmstate_pl110_post_load,
     .fields = (VMStateField[]) {
         VMSTATE_INT32(version, pl110_state),
         VMSTATE_UINT32_ARRAY(timing, pl110_state, 4),
@@ -430,6 +433,14 @@ static void pl110_mux_ctrl_set(void *opaque, int line, int level)
     s->mux_ctrl = level;
 }
 
+static int vmstate_pl110_post_load(void *opaque, int version_id)
+{
+    pl110_state *s = opaque;
+    /* Make sure we redraw, and at the right size */
+    pl110_invalidate_display(s);
+    return 0;
+}
+
 static int pl110_init(SysBusDevice *dev)
 {
     pl110_state *s = FROM_SYSBUS(pl110_state, dev);