r600g: cs init fixes

- all asics need to emit CONTEXT_CONTROL
- all r6xx asics need to emit 3D_START_CMDBUF

The ddx and r600c already do this. r600g should as well.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
diff --git a/src/gallium/winsys/r600/drm/r600_priv.h b/src/gallium/winsys/r600/drm/r600_priv.h
index 2e6a437..d785ede 100644
--- a/src/gallium/winsys/r600/drm/r600_priv.h
+++ b/src/gallium/winsys/r600/drm/r600_priv.h
@@ -166,6 +166,7 @@
 void r600_context_reg(struct r600_context *ctx,
 		      unsigned offset, unsigned value,
 		      unsigned mask);
+void r600_init_cs(struct r600_context *ctx);
 /*
  * r600_bo.c
  */