drm: Initialize the AGP structure's base address at init rather than enable.

Not all drivers call enable (intel), but they would still like to use this
member in driver code.

Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/i915_dma.c b/drivers/char/drm/i915_dma.c
index 9e4fc96..842db32 100644
--- a/drivers/char/drm/i915_dma.c
+++ b/drivers/char/drm/i915_dma.c
@@ -757,7 +757,7 @@
 
 	dev_priv->status_gfx_addr = hws->addr & (0x1ffff<<12);
 
-	dev_priv->hws_map.offset = dev->agp->agp_info.aper_base + hws->addr;
+	dev_priv->hws_map.offset = dev->agp->base + hws->addr;
 	dev_priv->hws_map.size = 4*1024;
 	dev_priv->hws_map.type = 0;
 	dev_priv->hws_map.flags = 0;