gallium/i915: call draw_flush() in i915_flush()

src/gallium/drivers/i915simple/i915_flush.c

@@ -31,6 +31,7 @@
 
 
 #include "pipe/p_defines.h"
+#include "draw/draw_context.h"
 #include "i915_context.h"
 #include "i915_reg.h"
 #include "i915_batch.h"
@@ -44,6 +45,8 @@ static void i915_flush( struct pipe_context *pipe,
 {
    struct i915_context *i915 = i915_context(pipe);
 
+   draw_flush(i915->draw);
+
    /* Do we need to emit an MI_FLUSH command to flush the hardware
     * caches?
     */